Ever experienced uninstalling an Exchange server from the control panel, add/remove program option directly? If you had, you would have noticed that sometimes it fails to do so. There are a lot of possible causes for this but the most common one is that Exchange server is unable to communicate with the DC. So you need to manually undo the changes that the Exchange Server installation setup makes to your machine and then uninstall it from the Control panel.
Exchange 2010 has send connectors so in order to uninstall Exchange 2010 they need to be removed apart from this you need to move your current mailboxes to another Exchange Server or disable them depending on whether you need to back them up or not. Lastly you might also need to uninstall a few updates. Once you are done with all these things, the installation would hardly take 35 minutes.
1) Open the Exchange Management Console
2) Go to Organization/Hub transport and select the Send connector tab and remove it
3) (Do this if you want to move your mailboxes to another Exchange Server i.e. create a backup of your current mailboxes) Open Mailbox and right click to select the option: Move all mailboxes. Now open the exchange management shell and run the move cmdlet.
Get-Mailbox -Arbitration -Database db1 | New-MoveRequest -TargetDatabase db2
4) (Do this if you want to remove and disable all current mailboxes) Open Mailbox and right click to select the disable option. Now open the exchange management shell and run the remove cmdlet.
Get-Mailbox -Arbitration -Database db1 | Remove-Mailbox -Arbitration –RemoveLastArbitrationMailboxAllowed
5) Normally Exchange Server install the update Exchange Update Rollup 3, this must be manually uninstalled from the control panel in the start menu. Clicks uninstall a program and click View updates in the left panel. Once you have unistalled this, the system will prompt you to restart, decline that message.
6) Go to start menu again and open the cmd.exe and type the command: ServerManagerCmd -i RSAT-ADDS
A few warnings might log up but they can be ignored because the connectors are not available anymore.
7) Now you can restart the server and preferably the machine too
8) Go to start menu|control panel|uninstall a program and select Exchange Server 2010
9) In the pop up uninstall window, uncheck all management tools and roles, click next till you reach finish and there it is. You have successfully uninstalled Exchange 2010.