The “workarounds” are useless and do not solve anything. All the results you will find on Google to this question are bogus, except for this one now. It has nothing to do with your client, or hot fixes, or your firewall or your antivirus. IN SHORT, THE WORKAROUND IS: To open your e-mail in Outlook Web Access (OWA), or via Exchange, and delete any meeting requests in your inbox.
But, at least it is a way of dealing with it. Unfortunately, what I have is not a solution as this appears to be an MS issue that is as yet unsolved.
According to the technet forum post, it will occur on any client (Thunderbird, Fetchmail, etc). Every time I received a new message, etc. This error for me occurred any time I tried to do anything in the inbox. The error you may receive is: Failed to update headers. I wanted to re-post what I found there in case it is of use to anyone else out there. I searched a ton of forums and couldn’t find a solution, but finally found something on TechNet. I had this issue for a long time with an Exchange account I was using on IMAP.
