Error messages that state that Gmail is unable to attach files may occur if an older version of the Flash plug-in is installed on the computer. The latest version of Flash can be downloaded from the official Adobe website. If Flash is blocked on the computer due to security settings, there may be issues when attaching files in Gmail. The browser should not be in offline mode to avoid problems when attaching files in Gmail. A different browser may be tried after disabling the proxy if Gmail is still unable to attach files.
Previously I was able to attach files to a Gmail message. Now I get an error message immediately that states it is unable to attach the file. I am using a recent version of Firefox. Please help!
If you're seeing error messages while uploading attachments, make sure you have Flash installed. Visit http://get.adobe.com/flashplayer/ to check for updates and download the latest version.
In addition, please make sure that Flash is not being blocked on your computer. If your computer's default browser is Internet Explorer, make sure that it's not in "offline mode."
Please note that this feature is not supported on Linux.
If you're using Flash 10, try these troubleshooting steps (note that you may not need to do all of the things listed below to fix the problem):
Switch your attachment settings from 'Advanced attachment features' to 'Basic attachment features' (click Settings and select the General tab to change this setting). Save your changes and try to upload your attachment again.
Try another browser.
Disable your proxy.
If you continue to have trouble after following these suggestions, report it here.