Rob - thanks for the response!
With the help of Symantec Support a colleague of mine resolved the issue resolved last night.
The notes from support are as follows:
ROOT CAUSE ANALYSIS:
EV OWA Extensions was not installed on the backend exchange server correctly, the control files under C:\Program Files\Exchsrvr\exchweb\6.5.7651.60\controls\ were not updated to EV 8.0.4.
The encoding type of evserrvers.txt was not Unicode, the EV server was not added to Bypass list.
SOLUTION:
Uninstalled OWA Extensions and saved evservers.txt file as Unicode, re-installed OWA Extensions on the backend exchange, EV buttons are available, user can delete items and archived items can be opened.
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A couple comments I'd add in case anybody comes across a similar problem in the future -
- The back story to our problem is that, despite having installed the OWA extensions on our Exchange server, we found initially that the expected icons weren't appearing in Outlook and archived documents couldn't be viewed (the "this message has been archived banner appeared instead"). This turned out to be due to missing "system mailboxes" in the Information Stores on our Exchange server. We found that by creating new stores and moving users to these stores that the system started working as expected. Note, however, after new stores are created, the "OWA + RPC" EV tool needs to be run on the Exchange server.
- Despite the wrong version of the OWA extentions being installed on the server and the system mailbox that had been affecting us, for the users that had been migrated to the new Information Stores (ie. those that did contain the required system mailboxes), everything seemed to work fine - except that users couldn't delete documents from the "inbox level" - only from within the document itself.
