We are using BES 4.1 on a Windows 2k3 R2 SP2 domain controller. The exchange server is on a separate box. A user has complained that he is not able to send emails to certain email addresses, specifically addresses that are internal. He is able to send emails to external addresses. He gets the error: "Message Status: User is in invalid mode." Another great error message from blackberry. Anyone have experience with this issue? Here is what I have done and determined:
-He can send emails to external addresses
-He can receive emails
-I have resent the IT policy and service books
-There are no errors in the event logs that I can see that would indicate an issue. I checked the BES server and the exchange server logs.
Are you actually running BES on the same server that performs your DC functions??
unfortunately small businesses sometimes don't have the luxury of having a standalone BES server. The exchange server is a DC as well but we chose not to install BES on that although we have for clients that only have an SBS server.
Like the article that DathBBerry posted, check which service is being used when sending internally. When composing a new message check the Using field at the top, it should be Desktop[Secure]. If it shows an email address, , then it's a BIS account.
I went onsite and looked at the phone. After a few minutes of fiddling I found that the issue was because the Send Using field was set to the wrong item. It's supposed to point to Desktop.
Message Status: User is in invalid mode. 
