This is a very strange problemI was installing Exchange 2007 on a network, which apparently installed correctly. I then created a few mail databases and mail enabled some users to test AD integration. No problem, i thought, i was able to enable users in different OU'sThen, after a reboot of the exchange box i was unable to log back onto the domain... as was everyone else, all 1000 users.The error everyone was getting was alone the lines of make sure your username and password are correct. A Microsoft support call was unable to see any problem as that error is only displayed when someone enters the wrong password. (Three were over 1000 users unable to log on, so thats not right)As of right now, no users what-so-ever can log on, and no-one can access AD to see the problemSadly this company do not back up AD, AD had replicated between all DC's and shadow copy was not enabled on either DC to access previous versions of the AD dit database.The DC's are up and running and DNS DHCP et al are servicing the network correctly. Basically, what can i do??No users can log on and no one can access AD to see why....It seems like all users have been disabled or their passwords changed on mass somehow?I am assuming it is Exchange 2007 related as the local technicians assure me they were not doing anything AD related at the time....Thanks for any help offered, obviously this is a mission critical issue for us

Dear customer: First, it is recommended that install Exchange Server 2007 form local not over LAN or WAN. Because setup over LAN may cause some issue such as access denied. If your issue is very urgent, you can contact local Microsoft telephone support. If you would like to use forum I can also provide support for you in the forum. To proper assist you to troubleshoot the issue, please help collect the following information: 1. After a reboot of the exchange box i was unable to log back onto the domain, please ensure you input the correct username and password that have corresponding administrative privileges. Send the screenshot of the error to v-rocwan@microsoft.com for analyze. 2. Try to log onto Exchange server 2007 with backup domain admin user, and check the effect. 3. Can you log onto the DC? Note: When you send e-mail to me please attach the subject of the post. Thanks for your time and cooperation. Rock Wang - MSFT