I am Dale Hayter, a Microsoft and VMware certified Technical Consultant.

My blog has been built up over the years from my experience of working on an IT helpdesk and also from being out on-site.

Exchange 2010 Sp3 – A Reboot from a previous installation is pending

When upgrading to Microsoft Exchange 2010 SP3 you might see the error below when it carries out its readiness checks.

A Reboot from a previous installation is pending. Please restart the system and rerun setup

Exchange Reboot1

So you reboot the server and try again…. same thing. No matter how many times you reboot it just will not install. This is a known issue and is caused by the PendingFileRenameOperations entry in the registry not being clear.

To clear this and successfully install SP3 go into the registry and proceed to the following key :

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager
Exchange Reboot2

Find the key PendingFileRenameOperations and double click on it.

Exchange Reboot3

Clear the contents of this box and click ok.

Now rerun the install of SP3 and it should now install ok.