Users may get error messages like “Attachment failed” or “Attachment failed. This may be due to a proxy or firewall” when they try to upload attachments to Gmail.

This guide is a collection of fixes and suggestions that may help resolve attachment failed type of messages in Gmail. Attachment failures have different causes, which means that there is no single fix available that resolves all the issues.

I suggest you try each method on its own by returning to the compose mail window and trying to add the attachment. If it works congratulations, you have resolved the attachment failed message. If it does not try the next option in line.

Attachment Failed Basic Help

You may want to try the following tips first before you try the advanced tips in the next section.

Adobe Flash

Make sure you are running the latest version of Adobe Flash. The default attachment uploader is using Flash for the uploading of files. Old Flash versions may no longer be supported by the uploader or return error messages.

Visit this page to check your Flash version and compare it with the latest version of Flash posted on the same page.

Web Browser

• Make sure you have the latest version of your web browser installed. Depending on your browser you can either check for updates directly in the browser, or need to visit the developer website to see if you are running the latest version.
• You may also want to consider switching browsers to see if that resolves the issue.
• Make sure your browser is not in offline mode, especially so if you are using Microsoft’s Internet Explorer.
• Try disabling the web browser proxy if one is configured.

Attachment Uploader

Gmail has an option to switch from the advanced uploader to a basic attachment uploader. This is done with a click on the gear icon in the upper right corner of the screen and the selection of Mail Settings. Locate Attachments under the General tab and switch from Advanced attachment features to Basic attachment features there.

Different Computer

Maybe you have access to a second computer, preferably at a different location. You can try to upload attachments on that computer to see if you experience the attachment failed issue there as well.

If you do not you know that it is not account related, but network or computer related. You may then want to check your firewall and security software settings to make sure that they do not interfere during attachment transfers to Gmail.

Advanced Tips Fixing Attachment Failed Messages

Desktop email

Using Gmail over the web is only one option for users. You can alternative download and install a desktop email client like Thunderbird or Microsoft Outlook. Configuration is not difficulty, see Setting Up Email Accounts In Thunderbird 3 for help on that.

Disabling HTTPS

Please note that it is usually not recommended to disable HTTPS. You may want to give it a try though if you have tried all other options.

You can disable it under the General tabs of your Gmail settings. Locate Browser Connection near the top and switch from Always use HTTPS to Don’t Always use HTTPs.

Contact Google

While there is no way of telling that Google will respond to your report, it may be better than giving up right away on resolving the issue.

Head over to the Gmail support contact form and send Google an email, telling them exactly what happens, and what you have tried so far.

Closing Words

There are lots of workarounds available to resolve attachment uploading problems on Gmail. If nothing helps, you may want to consider using a different email service after you have tested that attachment uploading works there.

Have you ever had problems uploading attachments to Gmail? If so, did you resolve those issues?

The extension makes it easy to extract multiple attachments at once. Just select all the mails that have the attachments that you want to extract and right-click afterwards. The option to extract them either to the default Thunderbird directory or to another location can be selected from the context menu. You may want to configure the attachment extractor further. You could for instance add potentially dangerous file types to a filter, add a default save path or define which action should take place if a file name already exists.

Installation is a little bit trickier than installing extensions in Firefox. You have to download the xpi file and install it directly in Thunderbird by going to Tools > Extensions > Install. Choose the downloaded file and it will be installed automatically at the next start.