Roughly two weeks ago Microsoft released Windows 7 Service Pack 1 to the general public. As is standard practice for most IT departments I held off on rolling out Windows 7 SP1 until any issues with the update had been identified. Since no issues have been identified that would affect the systems I manage I began rolling out the update this week. Unlike many of Microsoft’s previous operating system service packs, Windows 7 SP1 serves primarily as a roll-up of previous security updates. Still, there are a few updates included in SP1 that people will want to take advantage of — many of which are performance related. For whatever reason the update to SP1 hasn’t been as smooth as previous service packs. From what I’ve read on the interweb the installation of SP1 has become downright frustrating for many.
In many cases the update attempt simply ends with a vague error, Update error 800F0A12. I encountered this error on several computers I attempted to update. When I first experienced an installation issue I followed the normal troubleshooting steps. Disable anti-virus. Ok, I know, why didn’t I disable it to begin with? Well the simple truth is that most anti-virus solutions no longer interfere with software installations or OS updates. Unfortunately disabling anti-virus had no effect on resolving the error. Next step — Check for free space on the boot partition. Check — I had plenty of free space. Lastly, check for software that may be locking the disk and preventing the update from completing successfully. Nope, no software was present that could interfere in that manner. So now I was out of ideas. That was until I stumbled upon this article. Windows 7 utilizes a small system partition. This partition was not being automatically mounted and as a result the update to SP1 was failing. All I had to do was open a command prompt, running it elevated as Administrator, and type “mountvol /E” at the command prompt. Then I rebooted and voila — SP1 installed without a hitch. This same solution solved the error on all the computers I encountered the 800F0A12 error on.
If you experience difficulty installing Windows 7 SP 1 follow these troubleshooting steps.
- Make sure you a minimum of 1GB free space on the boot drive.
- Try disabling anti-virus and running the update again.
- Confirm that disk backup/cloning software is disabled and the associated services have been stopped. To view what services are installed on your computer and to stop services type “services.msc” in the search field or run line of the start menu.
- Make sure the system partition is being automatically mounted. You can insure the partition is being mounted by running a command prompt elevated as Administrator and entering “mountvol /E” at the command prompt. Then reboot and try the update again.
For more information see this article: http://windows.microsoft.com/en-US/windows7/windows-7-windows-server-2008-r2-service-pack-1-sp1-installation-error-0x800F0A12