I ama first time poster so hopefully I will put enough information in this question.
I am the Balckberry support for our company. We currently have several users who are having issues synching their blackberry calendar with our Exchange Server for Outlook. When they try to send meeting requests through the calendar on the blackberry, they get a red X and the email back. Also, if they update something in the Calendar, it never synchs with Outlook. They both can go into Outlook and create the meetings and the contacts and it synchs no probelm with the blackberrry. Also, from the blackberry, they both can send and receive email, and PIM messages just fine. The particular user I am woorking with is on a ATT Curve 8310, but the pther users are on Sprint and verizon, so it can't be carrier specific.. I have wiped the device and reactivated and also removed him from the server and did a re add but still gets the same error with trying to use the calendar from the Blackberry. I do know that a lot of patches were applied to our Exchange server this weekend, and I am going to email our network guys as well, so this may have something to do with it.
Has anyone seen this issue and/or know a possible solution? Thanks for any help.

When you open the message with the red X, what does it show next to status?

And welcome to the forums.

This question would be better answered in our BES related sub-forum.