Yesterday we had a mishap in which accidental deletion took place of user accounts within Microsoft Exchange 2010. The aim goal was to remove mailboxes, then databases and uninstall Exchange. However not realizing at the time, upon removing the mailboxes this deleted all active directory accounts. At this point the Microsoft Exchange 2010 server was then shutdown and left powered off.
We then restored our Windows Server 2012 R2 Domain Controller to the previous nights backup to restore AD, this was the only option as AD recycle bin was not yet enabled. After clean up of the Domain Controller the network is now in a healthy state and all is well again.
However coming back to the Exchange server we are not sure what will happen if this server is powered back on, will this effect AD in a form of sync? Or will this just sit with detached mailboxes as it was left. If there is no harm in booting the Exchange server back up can we then continue with the decommission of Exchange server?
Luckily we did take a full backup of the Exchange server before anything mailboxes were removed, so if it is better to first restore the Exchange server and then carry out proper decommission please could you advise?