BES Calendaring Weirdness

This has only happened with one client. So, I'm not sure how widespread it is. However, based on Googling the issue, it seems to be pretty frequent.

Some users were getting a red X when attempting to reply to meeting requests. Also, some meetings were not being synchronized properly.

To resolve this issue we had to update the cdo.dll file on the BES server. The version on the Exchange server was relatively recent. The version on the BES server was several years old. Apparently it is a best practice for BES to use the most recent cdo.dll file from any of your Exchange servers.

The steps to resolve were:

1. Copy C:\program files\exchsrvr\bin\CDO.dll from Exchange server to BES server (same path.
2. Reregister the dll (regsvr32 cdo.dll)
3. Restart BES server (probably could just restart services, but why mess around)

Problem resolved.