Microsoft Exchange Server 2010 R3

User reports that text is missing from messages she sends. She is not editing from the Preview Pane (see this thread: http://answers.microsoft.com/en-us/mac/forum/macoffice2011-macoutlook/outlook-2011-email-reply-forward-problem/8b5e2125-f7e4-487d-82f0-f120728252ee) and this has happened in new messages she's composed.

I have verified & repaired disk permissions, and rebuilt her identity in Office. The most recent iteration of this problem happened after those steps. I will update Office to v14.3.8 this week. The problem is not reliably reproducible - however I do have evidence of the issue.

In OWA the user's Sent Items display correctly, as she intended. They also appear correctly in her Sent Items folder in Outlook 2011. However recipients receive a message that is truncated or incomplete. I cannot yet find commonality to the missing text (it's not always copy/pasted in - sometimes it's typed - and it doesn't appear to be a formatting issue, as she's not changing the text size, font, etc. although she does use bulleted lists quite often; however it's not always only these lists that are missing; in one instance a numbered list had missing items and the list had been re-numbered to account for the removed text!).

I'm ready to rebuild her font cache and possibly remove & re-install Office, but if there's a fix or workaround I'd much prefer that option. I cannot find any evidence (in the form or errors or warnings) in the on-premise Exchange server logs. I have not yet attempted logging this user onto a different Mac to test whether the issue is consistent across machines.

Thanks in advance, I'm happy to answer any questions or clarify anything if I haven't provided the relevant information. This one is causing us major problems because we aren't certain that the user's messages are being received as she intends. I appreciate any ideas or advice.