Hi, Not sure which forum to post this on. We hav a client we recently installed a server for and are having problems with emails. The setup before was 4 desktops with shared files on one which they all worked off and they all had outlook and their own pop3 account. The shared files were getting too large so they wanted a server so we installed a server with Server 2008 SBS and made it a mail server as well. We setup exchange to get the mail from the pop3 accounts, added the desktops to the domain, imported all the emails from the local account to the domain account and everything works fine. They log in with the domain account created on the server then goto their exchange account in outlook and they can send and recieve emails no problem the issue is if they try to resend an old email they get an email back stating: From: Microsoft Exchange Sent: Monday, 5 July 2010 2:23 PM To: ######## Subject: Undeliverable: ################ Delivery has failed to these recipients or distribution lists: ###@### You are not allowed to send this message because you are trying to send on behalf of another sender without permission to do so. Please verify that you are sending on behalf of the correct sender, or ask your system administrator to help you get the required permission. Diagnostic information for administrators: Generating server: ###@####MSEXCH:MSExchangeIS:/DC=local/DC=ms:MECH[578:0x000004DC:0x0000001D] #SMTP# I am not familiar with exchange and the othrrs here have never come across this problem when installing a server before.

Hi, As this issue is related to Exchange Server, I suggest discussing it in our Exchange Server forum. They are the best resource to troubleshoot this issue. http://social.technet.microsoft.com/Forums/en/category/exchangeserver/ Tim Quan ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

TY did not see a forum specifically for exchange.