I have one phone that is working perfectly off of the BES and a second phone that is setup exactly the same, but is not working correctly.
Emails, contacts, calendar events, etc. all communicate perfectly down to the phone from Outlook through the BES, but I can't send or reply to emails from the phone and when I add something to the calendar on the phone it doesn't push up to my Outlook. And if I delete emails or calendar events on my phone or on my Outlook they don't delete on the other end.

I have deleted all desktop service books from my phone and resent them from BES. I have done a reset on the phone. I have double checked my BES settings. Yet nothing seems to be fixing the problems.

Any help is greatly appreciated!

Thanks,
Mike

You can only have one device on a BES account. Are you trying to have 2 BlackBerrys on the same account?

If it's a separate account you might need to update the software on the one that's not working and set up BES again from scratch on that particular BB. Every now and then you get one that just doesn't like BES. Often updating the software, or just re-installing the current OS, is enough to clear it up.

Can you confirm that Enterprise Activation completed successfully on the BB you're having problems with?

Thanks for the replies. I discovered the problem this morning. Because I am an Administrator on the network, the system kept automatically removing the BES account out of my security setting. I've made the necessary adjustment and all is well now.
Here's the link that describes the issue:
"..tp://blogs.technet.com/sbs/archive/2006/06/30/439685.aspx"