Email attachments in Outlook 2016 convert to an "ATT" file name followed by a number sequence (version1606.7070.20136 or later)

Important: This issue is now closed with the fix indicated below. For more information on other recent issues for your application, see Fixes or workarounds for recent Office issues.

Last updated: November 2016


Your email attachments might get deleted after you send your email, and the filename appears to the recipients as ATT<XXXXXX>, where <XXXXXX> is an arbitrary number sequence. This happens if you have added a digital signature to your message, but turn it off when sending your email.

Status: Fixed

This issue has been fixed in build 7369.2038. Please go to File > Office Account > Office Updates > Update Now, to install the update.

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See Also

Fixes or workarounds for recent issues in Outlook for Windows

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