Hi,

My user have his blackberry for a while now. Everything was working fine (send and receive, etc).

One day he was unable to send or reply email. We discover that the windows domain administrator right has been assigned to him. So we removed it. Resend Policies, Reboot servers and reload the user.

I don`t know what else to do. I am thinking of removing / delete the user from the BES or simply change Blackberry device.

Please help !

You need to re-apply the correct SendAs permissions for the user's mailbox.
http://www.blackberry.com/btsc/KB04422

They were likely revoked when the Domain Admin privileges were given to the AD user account.

Did it all right send as was there. .... removed and reapplied the send as ....
same problem.

The device also been wiped out!

Grep the MAST and MAGT logs for that user's userid which should reveal some 0x8--- errors that you can take to the KB and try to sort out.