When opening or downloading an email message with attachments in Gmail by Google, the following error message may appear above the email attachments after virus scanning completed:

Oops… the virus scanner has a problem right now. Download at your own risk, or try again later.

Cannot Download Gmail Attachments

It’s good if user can view or download the attachments. However, when user clicks on “View”, “View as HTML” or “Download” button of the mail attachments, the one of the following error message appears instead:

Temporary Error (500)

We’re sorry, but your Gmail account is temporarily unavailable. We apologize for the inconvenience and suggest trying again in a few minutes.

If the issue persists, please visit the Gmail Help Center.

We’re sorry, but your Gmail account is currently experiencing errors. You won’t be able to use your account while these errors last, but don’t worry, your account data and messages are safe. Our engineers are working to resolve this issue.

Please try accessing your account again in a few minutes.

Gmail Temporary Error 500

User is normally presented with options to try again or sign out. There is also detailed technical info which specifies error numeric code as 54. Attempt to download or save the attachment will also resulted a “Temporary Error 500” or “Temporary Error 502” and automatic page reloading or refreshing. The attachment is also not available offline.

If user tries to forward or reply the affected message with the attachment, the sending or mail delivery will fail with the following error message:

‘Oops… a server error occurred and your email was not sent. (#754)

Or, the sent email message has been placed in the outbox indefinitely. For user with offline Gmail feature enabled, the synchronization status will become erroneous and cannot sync properly with following message:

Status: Server error reported while synchronizing data.
There are pending changes that will be sent the next time you connect.

Gmail Sync Error Due to Virus Scanner

There are no known cause of causing the cannot and unable to download attachments error in Gmail, and Gmail doesn’t have any remedy or resolution to the issue yet. What can be sure of is that the attachments that causing the problem are mostly clean and not infected with virus or malware. One common symptom that may trigger the issue above is multiple emails that arrived about the same time and have attachments that have the exact same name. This may cause Gmail to treat the many email messages as just one mail, effectively disabling download access of attachments on e-mails that arrived earlier. Problem is also reported on attachment with encrypted contents, or normal files such as PDF, JPG, DOC, ZIP, PPT and etc that has binary pattern that screws up the anti-virus engine on Gmail.

As Google doesn’t even acknowledge the existence of the problem (it’s not listed as one of the Gmail known issues despite many users encounter similar error), so Gmail users are left to themselves to fix the error. There are a few workaround fixes and solutions that may help users to retrieve, recover and download the email attachments stuck in Gmail.

Workaround 1: Try Again Later

Oddly enough, some Gmail users reported that the error goes away after “a while”, which may mean not accessing Gmail at all for 24 hours and longer.

However, it’s not going to fix problem faced by many users. For user who continues to face unable to view or download attachments from Gmail for extended period of time, try other workarounds.

Workaround 2: Ask Sender to Resend the Attachments

Easy and straight forward solution, but not convenient, and potentially damage the image of Google and Gmail. It also doesn’t work if user is dealing with old emails whose sender no longer contactable, or source that automated email sending.

Anyway, resending of emails almost always work to enable download of the attachments.

Workaround 3: Use IMAP to Access Gmail to Download the Attachments

Most users encounter “Oops… the virus scanner has a problem right now. Download at your own risk, or try again later” error when using Gmail webmail user interface. By switching to IMAP access, individual email messages may be downloaded to email client, allowing the attachments to be saved.

To use IMAP, user will need a email client such as Microsoft Outlook or Thunderbird. The configure the email client to access Gmail via IMAP protocol (note: NOT POP3 which will “download and delete” the copy of emails on Google server, unless you don’t want web-based access to your emails anymore).

Gmail has a list of supported IMAP client with their setup instructions at http://mail.google.com/support/bin/answer.py?hl=en&ctx=mail&answer=75726

Workaround 4: Manually Base64 Decode the Attachments

Internet e-mails are delivered via SMTP in MIME (Multipurpose Internet Mail Extensions) format, which extends the format of e-mail to support text in character sets other than ASCII, non-text attachments, message bodies with multiple parts and header information in non-ASCII character sets. In MIME protocol, an attachments in email is encoded with Base64 for content transfer. By Base64 decoding the attachment part in MIME email, the complete attachments can be downloaded and retrieved.

  1. Open the email with problematic attachment in Gmail which user wants to download.
  2. Click on the Down Arrow button next to “Reply” or “Reply to all”, and select Show Original.

    Show Original Email Content

  3. The whole content email message will be opened in plain text format. Search for the file name of attachment using the Find or Search function of the web browser. It should stop at the lines or section which look similar like below:
    Content-Type: image/jpeg; name=snap.jpg
    Content-Disposition: attachment filename=snap.jpg
    Content-Transfer-Encoding: base64
    .......... truncated as for example only.........
  4. Copy and paste the huge block with gibberish text of base64 MIME encoded to a text editor, and save it with the name of the attachment.

    Hint: Start with the line right after the blank succeeding all the Content-X declaration, to the line right before the last time with starts with multiple dashes (—————–).

  5. Decode the file with any Base64 decoder. For example, web based Base64 decoder at http://www.motobit.com/util/base64-decoder-encoder.asp.

    User who wants to ensure privacy and confidential can download standalone base64 encoder and decoder utility such as Notepad++ (copy and paste into Notepad++, highlight all text, then select Plugins -> MIME Tools -> Base64 Decode) or http://www.fourmilab.ch/webtools/base64/base64.zip to perform decoding offline. Unpack the ZIP archive to get base64.exe and run the following command in a Command Prompt window (ensure that you change directory or CD to the folder with base64.exe):

    base64 -d -n source_input.txt attachment_name.pdf

    Note: Specify the full patch to input source file (file with base64 encoded text from email attachment) if the file and base64.exe executable are not in the same folder.

  6. Open the downloaded attachment.