This issues was occurred since 2012 and was discussed at answer.microsoft.com with no answers:

http://answers.microsoft.com/en-us/mac/forum/macoffice2011-macoutlook/outlook-2011-1421-address-corruption/ff5fe54b-e79c-480c-ae55-c9a109fb42e0?auth=1

After upgrading to 14.2.1, from 14.0.0, Outlook keeps putting an orange question mark to the left of any email address within my exchange organisation (Our email service provider has several exchange server, mailbox may install at different servers), but only when replying to a message.  When this happens and I hit send, messages never arrive at the intended mailbox, and there are no NDR messages.  Any Ideas?

Details:

1) Question Mark beside the sender showing that no email address found. Can't forward or reply to the sender, have to manually enter the email address. 2) Mac Outlook version 14.1, Windows Outlook 2013, OWA and POP, IMAP service no such issues. Only happen when using MAPI.

3) Header showing the sender's email address but Outlook seems can't recognized.

4) It happens in some organisation (same domain) but have multiple Exchange servers.

Please advise how to fix this issues as all the Outlook Mac 2011 stays at version 14.1.4 and could not update.

Thanks

Ricky

Hi Ricky,

I understand that the issue only occurs to Outlook for Mac 2011, but in this forum we only discuss questions and feedbacks about Outlook for Windows, I'm not familiar with Outlook for Mac 2011 so there is quite few suggestion I can provide, so I suggest you post a new thread in the Office for Mac forum:

http://answers.microsoft.com/en-us/mac/forum/macoutlook?tab=Threads

Regards,

Melon Chen
TechNet Community Su