Can’t Open an Email Attachment? Fixes and Tips

Ever screamed in frustration when an important email attachment won’t open? You’re not alone! In this ultimate guide, we’ll show you how to troubleshoot and fix the “can’t open attachment” issue once and for all.
Discover what causes attachments to fail, step-by-step techniques to open them, mobile-specific fixes, best practices, and when to call in the experts. Say goodbye to uncooperative attachments and missing file disasters with these handy tips. Let’s do this!

Common Causes of Email Attachment Issues

Opening an email only to find you can’t view the attachment is frustrating! But don’t worry, it happens to all of us. Here are some of the most common reasons email attachments don’t open:

File Format Not Supported

This is one of the top reasons you may see an error when trying to open an attachment. If the file format isn’t supported by your device or apps, you’ll get blocked.

Some examples of popular formats that could cause issues:

  • .EXE application installers – these run executable code so most mail apps block them for security.
  • .ZIP compressed files – need an app like WinZip or built-in unzipping to open these archives.
  • .PSD Adobe Photoshop files – require having Photoshop installed to view this format.
  • .PAGES Apple Pages documents – can only be opened on Macs with the Pages app.

If you’re getting format errors, first check if you have the necessary software installed to open that file type. For example, make sure you have a PDF reader like Adobe Acrobat to open .PDF documents.

If you don’t have the right app, try installing one that supports the format or asking the sender to export or “Save As” another format you’re able to open. Popular cross-platform options include .PDF, .JPG, .TXT, .MP3.

Attachment Corrupted or Damaged

While less common, attachments can sometimes become corrupted or damaged during the email upload or download process. Signs of a corrupted attachment:

  • Error messages like “File is corrupt and cannot be opened.”
  • Attachment preview thumbnail shows garbled or unintelligible images.
  • Email client crashes or freezes when trying to open the file.
  • The file size of the attachment is very small, often only a few KB.
  • Double clicking on the attachment does nothing or displays gibberish.

Some things to try if an attachment is corrupted:

  • Ask the sender to resend or reupload the file.
  • Try opening the file on a different device like a smartphone or tablet.
  • Copy the attachment to your desktop first before attempting to open.
  • Open the file in a text editor like Notepad to see if any data is recoverable.

If it’s completely unrecoverable, there’s unfortunately not much you can do besides asking the sender for another copy. Make sure to add .ZIP or another archive format when re-attaching to protect file integrity.

Large File Size Causing Download Failure

Ever clicked an attachment that gets stuck at 99% downloading forever? Chances are the file size was too big, causing the transfer to time out or fail.

Many email providers place limits on attachment sizes, usually around 25MB or so. Exceeding this causes problems not only downloading but also uploading on the sender’s side.

If you consistently deal with large files like videos, design files, or sheet music, consider alternative transfer options. Some fixes include:

  • Ask the sender to split attachments into smaller chunks to avoid limits.
  • Use a file sharing service like Dropbox or WeTransfer to send big files.
  • Save the attachment to cloud storage instead and share a download link.
  • Compress the attachment using .ZIP, .RAR, or another archiving format to reduce filesize.
  • Upload the file to YouTube privately and email the link if it’s a large video.

And for receiving, increase your email account’s attachment size limit if possible in the settings.

Blocked by Security Software

Antivirus programs and firewalls can sometimes block email attachments from downloading or opening. They may falsely flag a perfectly safe attachment as suspicious or malicious.

If your security software pops up alerts for an attachment, you can either:

  • Add the file to exclusions so it’s always allowed.
  • Temporarily disable protection to open the block attachment.
  • Download the file first rather than opening directly from the email.
  • Ask the sender to password protect or ZIP the attachment to bypass filters.

Keep in mind that disabling security is risky if the attachment really is dangerous. Use best judgment before ignoring warnings.

If the sender’s email domain is on a blacklist, that can also trigger attachments from them to be auto-blocked. But this is less common from reputable companies.

Storage Limit Reached

Email attachments may fail to download if you’re low on storage space. Whether it’s your mail app’s storage limit or hard drive space, exceeding capacity prevents saving or opening files.

On mobile devices, not having enough free local storage is also a common reason attachments get stuck. For iPhones, the “email cannot be downloaded because there is not enough available storage” error pops up.

Some ways to fix an over-capacity storage issue:

  • Clear space on your hard drive by deleting unused files and programs.
  • Upgrade to a larger hard drive if you need more room.
  • Turn on storage optimization in your mail app’s settings if available.
  • Delete older large attachments you’ve already saved elsewhere.
  • Move attachments to a cloud sync folder like Dropbox to save local space.
  • For mobiles, offload unused apps or old photos using built-in device storage management tools.

Keeping plenty of free space is key to ensure attachments transfer without errors. Monitor your storage usage levels and clean up any unnecessary files.

Following the troubleshooting steps in this section should help identify and resolve the root causes of most stubborn email attachment problems. Let’s now move on to solutions you can implement when attachments won’t open.

Troubleshooting Steps to Open Attachments

Tried everything but still can’t get that important attachment open? Don’t panic! Here are some step-by-step troubleshooting tips to solve the problem once and for all.

Check File Format and Install Software

First, confirm the file format based on the extension (.PDF, .DOCX, .MP4 etc). Then make sure you have the necessary software installed to open that format.

If it’s an uncommon format, search online for “How to open [file format] files on Windows” to find a compatible program. Here are some common examples:

  • Pictures: .JPG, .PNG, .GIF – Preview pane in Windows. Alternatively try basic image editors like Paint, Paint 3D, or Paint.NET.
  • Documents: .DOC, .DOCX – Install Microsoft Word, or use the free Word Viewer.
  • Sheets: .XLS, .XLSX – Install Microsoft Excel, or use the free Excel Viewer.
  • Presentations: .PPT, .PPTX – Install Microsoft PowerPoint, or use the free PowerPoint Viewer.
  • PDF Files: .PDF – Install Adobe Acrobat Reader or other free readers like Foxit.
  • Video Files: .MP4, .MOV, .WMV – Install VLC Media Player or Microsoft Movies & TV app.
  • Audio Files: .MP3, .WAV, .WMA – Install VLC Media Player or Windows Media Player.

Without the proper software, the attachment simply won’t open no matter what you try. Install any required programs if missing.

Download and Save Attachment First

Instead of opening attachments directly from the email, try saving them to your Downloads folder first:

  • Right click the attachment and choose Save As or Download.
  • Or click to open the attachment and then save using File > Save As in the viewer program.

Saving attachments separates them from the email client, eliminating any email app conflicts. Then you can double click the saved file to open in the appropriate default program.

This also helps for viewing attachments on mobile devices. iOS and Android don’t allow directly viewing from the email. You must tap to download, then go to Files or File Manager to open the attachment after saving.

Scan for Viruses

It’s possible your antivirus mistakenly quarantined or blocked the attachment even if it’s safe. Scan the file with your antivirus program according to its instructions.

If it discovers issues, it will clean or repair the file. If nothing turns up, you can add the file to exclusions as a workaround.

Also try downloading the attachment with antivirus and firewall temporarily disabled. Re-enable protection after verifying there’s no threats.

Change Security Settings Temporarily

Increase permissions for your email client attachments as a test:

  • Outlook desktop attachments:
  • File > Options > Trust Center > Attachment Handling
  • Uncheck “Don’t allow attachments to be saved or opened that could potentially be a virus.”
  • Gmail attachments:
  • Click Gear Icon > Settings > See all settings > Attachments
  • Uncheck “Ask before opening attachments”
  • Increase attachment max size
  • Outlook Web App:
  • Click Gear Icon > Options > Attachments
  • Select “Allow attachments from trusted senders”

If an attachment works after tweaking security settings, remember to revert the changes after troubleshooting. Leaving extra permissions enabled long term creates risk.

Clear Browser Cache and Temp Files

Corrupted temporary cached files related to the email attachment could be an issue. Clearing these fixes problems surprisingly often.

  • Clear browser caches: Delete temporary internet files and history in Chrome, Safari, Firefox, Edge, etc.
  • Delete email app caches: Close all email apps and delete their temp folders. For Outlook it’s under AppData > Local > Microsoft > Outlook.
  • Empty general temp folders: Like %temp% and %tmp% under AppData and User folders.
  • Run Disk Cleanup: Use the built-in Windows Disk Cleanup utility to wipe unused Windows downloads and other temporary files.

After deleting caches, restart the computer and try the attachment again. If it now works, you know the issue was corrupted tmp files hogging space or causing conflicts.

Use a Different Browser or Computer

Another idea is to eliminate software conflicts by viewing the attachment in an entirely different environment.

For example, try opening the non-working attachment:

  • In a different web browser like switching Chrome to Firefox.
  • On another device like a mobile phone or tablet.
  • On a separate computer running the same operating system.
  • On a separate computer running a different OS like Windows vs Mac.

If the attachment opens fine in a fresh browser or device, then it’s an issue with that particular software setup. Reinstalling the affected application often fixes these incompatibilities.

This trick also helps diagnose if it’s a global file corruption. If the file doesn’t open anywhere, the data itself is likely damaged or truncated and a new copy is needed.

But if it only fails in one spot, it’s just an isolated software conflict or configuration issue.

Hopefully one of these universal troubleshooting tips resolved your frustrating attachment problems! Let’s move on to solutions tailored for mobile devices next.

Attachment Won’t Open on Mobile

Mobile email can be tricky when dealing with attachments. Limited storage space and finicky apps cause frequent issues opening files on smartphones and tablets.
Here are some quick fixes to try when an email attachment gets stuck or fails to open on your iPhone, iPad, or Android device.

Update the Email App

Outdated app versions often lose compatibility with newer attachment formats and files. Upgrading to the latest release fixes many problems:

  • On an iPhone or iPad, open the App Store and check for any available updates to the Apple Mail app.
  • On Android, open the Play Store and update Gmail, Samsung Email, Outlook, or whichever mail app you use.

App developers frequently patch bugs and improve attachment support in updates. Keeping core apps like email fully updated eliminates many common issues.

Enable Downloads in App Settings

Most mobile mail apps don’t let you open attachments directly for security reasons. You first need to download or save them before viewing.

Check your email app settings to confirm attachments downloading is enabled:

  • iOS Mail app:
  • Settings > Mail > Disable “Restrict Attachments” and “Block Dangerous Attachments”
  • Gmail app:
  • Tap hamburger menu > Settings > Enable “Auto-download attachments”
  • Outlook app:
  • Tap menu > Settings > Enable “Download Attachments”

If your email app lacks an attachment download setting, your only option may be manually saving each one before opening. Annoying, but at least attachments won’t mysteriously fail anymore!

Check Available Storage Space

Perhaps an obvious fix, but make sure your iPhone or Android isn’t completely out of storage. Downloading and saving attachments requires available space.

The easiest way to check is try saving a test photo from the web. If your device is full, it will fail and show a storage limit message.

To clear up room:

  • Offload unused apps
  • Delete old photos/videos
  • Manage messages and attachments
  • Upgrade iCloud storage if you use it
  • Transfer files to cloud storage or computer

Once you have breathing room, email attachments should download flawlessly even if they’re large in size. Maintaining ample free space is key for mobile file transfers.

Open File Manager App First

Here’s an issue many run into — you download the attachment successfully, but then can’t find it after! It’s there, just hidden.

On an iPhone or iPad, don’t look for it in the Mail app itself. Instead go to Files > Downloads folder.

On Android, open the Files or My Files app and check the Downloads folder.

It’s poor UX design, but email apps silo attachments. The OS file manager handles all downloads, so that’s where you need to look on mobile.

Connect to WiFi for Large Attachments

If an attachment stalls out mid-download, it’s likely too big for mobile data speeds. The connection times out before the transfer finishes.

The easiest fix is to wait until you’re on a fast WiFi network and try downloading the attachment again.

Mobile data may only support up to 10MB attachments typically. But on WiFi you can easily transfer much larger 500MB+ files without timeouts.

For super big attachments, save them to cloud storage like Dropbox or Google Drive instead. Rather than directly downloading, have the sender upload the file to cloud storage and then they can share the link with you. No attachment size limits!

Those are your best options for dealing with stubborn attachments that refuse to play nice on mobile. With this advice, you can troubleshoot and solve most issues that pop up.

Still Can’t Open Attachment? Additional Fixes

Exhausted all the typical troubleshooting suggestions but still unable to open that important attachment? Don’t lose hope yet! Here are a few more sophisticated techniques to try:

Ask Sender to Resend or Reupload

If you’ve determined the attachment itself is the issue, request the sender resend it. Here are some specific tips to pass along:

  • Try sending the file in a different format like .PDF instead of .DOCX.
  • Re-export the attachment from the original files if available. The export process could have corrupted it.
  • Zip/compress the attachment before sending to protect integrity.
  • Attach the file to a new blank email instead of forwarding the chain.
  • Double check the true file size – a tiny KB attachment is likely truncated.
  • Upload to cloud storage instead of attaching if very large.

Hopefully getting a fresh copy of the attachment sent again does the trick. But if not…

Compress File Size Before Sending

Big attachments closer to the 25MB email size limit are more prone to corruption or download failure.

Ask the sender to ZIP the attachment first – this compresses it to a smaller filesize for safer transmission.

Popular archive formats like .ZIP, .RAR, and .7Z shrink large files down by 50% or more.

Just make sure to remind the sender to give you the password if there’s encryption!

Split Attachment Into Multiple Emails

Another workaround for a large attachment is to split it into smaller parts.

The sender can break up the file into chunks under 25MB using free file compression tools. Then attach each piece in a separate email.

You’ll need to recombine the split files after receiving everything. But it beats dealing with a massive attachment that never makes it through.

Use a File Sharing Service

If all else fails, sidestep email attachments entirely. There are web services designed specifically for transferring large files:

  • Dropbox – Both parties need accounts, but easy drag and drop uploads/downloads.
  • Google Drive – Share files up to 5TB. Works even without Google accounts.
  • WeTransfer – Free for files up to 2GB, no sign up required. Expires after 1 week.
  • Microsoft OneDrive – Straightforward cloud storage + sharing.
  • Box – Upload and preview files. Reviewers can add comments.

These services don’t have attachment size limits or security scanning getting in the way. Great workaround if email gives you fits!

Hopefully with one of these additional troubleshooting tips you finally slay your attachment demon. But if not, it may be time to escalate the issue and get an expert involved. Let’s discuss that next.

Best Practices for Sending and Receiving Attachments

Even when everything’s working fine, there are some habits that can prevent future email attachment headaches.
Follow these simple best practices to make life easier on both the sending and receiving end:

Confirm Recipient Can Open Your Formats

Don’t assume the recipient’s device can open the attachment format you’re sending. Always verify first.

Common questions to ask before attaching:

  • What operating system do you use – Windows, Mac, Linux?
  • Do you have software that can open [file format]?
  • Would you prefer I send this as a PDF/JPEG/text file instead?
  • Does your email platform block certain attachments like EXE files?

Taking a minute to confirm software compatibility eliminates issues down the road. Offer to export the file to a cross-platform ready format they can easily open.

Zip Large Files Before Attaching

When attaching anything over 10MB, first compress the file to reduce the size.

Using ZIP, RAR, 7Z and other archive formats significantly cuts down large files. This prevents:

  • Hitting attachment size restrictions
  • Transmission corruption or timeouts
  • Overloading the recipient’s mailbox storage

The smaller compressed size also finishes downloading much faster on the receiving end.

Double Check Filenames Before Sending

Seems simple, but incorrect filenames cause all sorts of confusion:

  • Make sure the attachment file extension (.DOCX, .PDF, etc) matches its content. Don’t label a PDF as DOCX.
  • Keep filenames short, descriptive and without special characters that different operating systems may interpret incorrectly.
  • Verify the file extension indicates the actual format. Sometimes .ZIP files get renamed .DOC for example.

Taking a second look at filenames alleviates the “Wait…what format is this attachment again?” issue recipients may have.

Ask Recipient to Confirm Receipt

Don’t assume the email attachment made it safely. After sending, politely ask if the recipient can preview or open it without any problems.

If they reply that it won’t open, you can quickly jump on troubleshooting before the matter slips your mind. Or resend the attachment while the issue is top of mind.

Having the recipient confirm proper receipt the moment they get it can nip many problems in the bud.

Protect Personal Information in Attachments

When sending attachments containing sensitive information like financials or legal contracts, take steps to protect the content:

  • Password protect documents and spreadsheets if the software supports it. Provide the password separately from the attached file.
  • Convert files to an Adobe Protected PDF with encryption enabled.
  • Use a digital rights management (DRM) tool to control viewing access.
  • Zip the file with encryption before attaching. Again provide the password separately.
  • Mark emails as “Confidential” and remind recipients to be cautious if printing or forwarding.

With all the high profile email leaks and data breaches, it pays to be prudent with attachments containing private info. Apply a “better safe than sorry” approach.

That covers the major best practices for smooth sailing when sending and receiving email attachments. Now let’s quickly discuss when it may be time to escalate matters and call in an expert.

When to Seek Expert Help

Stuck troubleshooting an attachment issue that you just can’t crack? At a certain point, it pays to hand things over to a professional.
Consider escalating matters and seeking help if:

Attachment Issues Persist After Troubleshooting

If you’ve tried all the standard advice but attachments still refuse to open, you likely need specialist assistance.

Exhausting your own efforts is when it’s reasonable to seek an expert’s knowledge and tools.

Don’t let the problem fester unresolved – the sooner it’s fixed the better.

Suspicious Attachments or Links

In rare cases, relentless attachment trouble could signal something nefarious at play:

  • An attachment you can’t open no matter what could be malware or ransomware, especially if coming from an unknown sender.
  • Links to shared files that require special permissions or software may be a phishing scam.

If an attachment seems suspicious, don’t ignore red flags. Have an expert scan it in a controlled environment to assess risk.

Potential Malware or Virus Infection

Similarly, if attachment issues strike multiple computers company wide, it may indicate a wider virus or malware outbreak spreading through shared files or links.

Sudden epidemic attachment problems call for swift containment and remediation measures only an expert can provide. Don’t take chances.

Multiple Users Unable to Open Attachments

Are colleagues all experiencing the same mysterious attachment difficulties? It’s probably an underlying email app misconfiguration or flawed file association.

Rather than waste hours troubleshooting individually, have IT support investigate the root cause centrally and roll out a global fix.

Finally, consider seeking expert help for:

  • Advanced file recovery or restoration
  • Desktop client reinstallation, profile resets
  • Server-side configurations and permissions
  • Malware detection and system cleaning

Sometimes DIY options are exhausted and you need seasoned professionals wielding more advanced tools. Know when to pass the baton.

Key Takeaways: Open Email Attachments Without Issues

Dealing with attachments that won’t open in email can be incredibly frustrating. But armed with the right knowledge, you can troubleshoot the problem and get access to those critical files.
Here are the key tips to remember:

  • Identify the file format and install any required software needed to open it.
  • Save attachments to your desktop first before trying to open.
  • Temporarily disable antivirus if it’s blocking attachments.
  • Attachments over 25MB often fail – ask the sender to use file compression or cloud sharing.
  • On mobile, make sure storage space is available and use the Files app to open.
  • Can’t open after troubleshooting? Request the sender resend the attachment.
  • Split up large attachments into smaller parts if they fail to transmit.
  • Password protect sensitive documents before attaching in emails.

Don’t waste hours fighting with an attachment. Follow these tips to solve the issue quickly. And know when it’s time to escalate and get expert assistance.

You’ve got this! Before long you’ll be opening email attachments smoothly every time.

Here are some frequently asked questions about troubleshooting email attachment issues:

FAQs: Troubleshooting Email Attachments

Q: Why can’t I open attachments in Gmail?
A: Common reasons Gmail attachments won’t open – disable antivirus scanning attachments, allow less secure apps in settings, update your Gmail app, or save attachments to your desktop first before opening.

Q: How do I open attachments on my iPhone?

A: You can’t directly open email attachments in the iOS Mail app. First tap to download the attachment, then go to Files app and open it from the Downloads folder.

Q: The attachment size is 0KB – how do I fix it?

A: A 0KB attachment is truncated and corrupted. Ask the sender to resend, compress it first, or use a cloud sharing service instead of attaching directly.

Q: What does “attachment blocked by security” mean?

A: Your antivirus or internet security suite is blocking the download. You can disable it temporarily to grab the file, or exclude the attachment from scanning.

Q: Why does my attachment open as a random character string?

A: The file is corrupt. Ask the sender to re-export and resend the attachment. Also save it to your desktop first instead of opening directly.

Q: The attachment format cannot be recognized – what should I do?

A: Install software capable of opening that file format. For example, download Adobe Acrobat Reader to view PDFs.

Q: How can I tell if an attachment is malicious?

A: Signs include coming from unknown senders, having multiple extensions like NAME.PDF.EXE, asking you to enable macros, or requesting admin permissions. Use extreme caution.

Q: What causes the “attachment could not be downloaded” error?

A: Issues like expired temporary download links, interrupted internet connections, blocked files, exceeded size limits, or full mailbox storage.

Q: How do I open Winmail.dat attachments in Gmail?

A: Winmail.dat files are used by Microsoft Outlook. You need to save the attachment and open it using Outlook on a Windows PC.