I have problem with Outlook for Mac 2011, specifically my sent file folder.  When I open (double click) sent emails the following fields are all editable: To, From, Subject and Attachment.  The sent file opens in resend mode.  As a result of this, when I reply to this message in a discussion thread, the reply date and time are not recorded in my reply nor are the reply arrows visible in my sent folder.  I have confirmed that these messages have been received.

I have rebuilt my database

I have created a new identity & resynch with Exchange

I upgraded 14.5.3

Problem still exists!!!

Any thoughts?

Thank you

I rebuilt the database and still had the same problem.

Today, I am unable to cancel a meeting, received the following error message "Unexpected data was encountered.  Mail could not be sent.   Error Code 17997.  

Appreciate any insights.