When using the Email Upload to a Folder feature in Box, it is possible that the file you attach will not be successfully uploaded. When an email upload to a folder fails, you will receive an email notification to alert you.
Troubleshooting Steps
- Are forbidden characters in the file name or signature images? See section below on Forbidden Characters.
- Is another item with the same file name in the folder? If so:- see whether "Overwrite files with the same name" is checked in the target folder settings
- see whether the existing item is locked, as this leads to failed uploads.
 
- see whether "Overwrite files with the same name" is checked in the target folder settings
- Is the sender email address associated with an unconfirmed Box account?- To find out, try to log in to the Box Web Application with the email address.
 
- Is the sender email address associated with a free Box account? And have you recently deleted the associated account?- The email address cannot be used as a sender email address for 120 days after the free account deletion.
 
- Is the target folder owner an active Box Account?
- Does the Box account of the target folder owner have available storage?
- Do you have SPF enabled? See notes on SPF at: Upload to Box Through Email
- This feature is not available to Starter accounts and Personal accounts.
- Upload via email only works for file attachments. Content in the body of an email is not uploaded to Box.
- The cumulative size of the message body and attachments (including signature) cannot exceed 50MB.
- Both the folder owner and sender will receive a notification that files were uploaded successfully.
- Collaborators will also receive a notification if upload notifications are enabled for the folder.
- Email uploads of ".msg/.eml" files through Microsoft Outlook desktop application fail due to how Outlook handles attachment of these file extensions. As a workaround, it is recommended that you compress these attachment types into a zip file before emailing.
- Box does not support TNEF, which is a proprietary email attachment format used by Microsoft Outlook. The attachment that is titled "winmail.dat" is ignored and is not uploaded to Box. For more information and the steps to disable TNEF, please refer to the Microsoft support page: https://learn.microsoft.com/en-us/troubleshoot/outlook/message-body/how-tnef-affects-email-messages
If you can't access the above information, or if you can and everything seems in order, please open a case with Box Product Support and we will help investigate further.
Here is what we need from you:
- The email address from which the email was sent
- The target folder's email address
- The file name you attempted to upload
- A date/timestamp (including time zone) of when the email was sent
Forbidden Characters
Some operating systems do not support item names containing special characters. If you attempt to save items containing these characters in the item name, you may get a failed email upload.
- Box OS-independent restrictions: - Box does not support '/' and '\' anywhere in a file name or whitespaces at the beginning or end of a file name.
- File names cannot contain non-printable ASCII. i.e. Linefeed, CR characters.
 
- Windows OS restrictions:- < (less than)
- > (greater than)
- : (colon)
- " (double quote)
- / (forward slash)
- \ (backslash)
- | (vertical bar or pipe)
- ? (question mark)
- * (asterisk)
- See the list of Windows file name restrictions
 
webapp_swarm_kb