Installation of SP2 requests SP1, which is already installed

Question

When I try to install SP2, Vista (Home Premium) asks to install SP1. SP1 however is already installed. In the system log is a message with errorcode 0x800f0a05.
I've tried both with windows update, as well as with the downloaded SP2 executable (Windows6.0-KB948465-X86.exe). Both give the same result. If I try to reinstall SP1, it gives an error stating that SP1 is already installed as is confirmed by Winver (SP1: Version 6.0, build 6001). SP1 does not show up in my list of installed updates, so I cannot uninstall it and reinstall it again.
I also tried to run the System Update Readiness tool but no error or change was given in the CheckSur.log.
The CBS log gives, among a lot of opther rubish the following:
009-08-10 19:33:15, Error                 CBS    SPI: (CSPICbsClient::OpenPackage:227)Failed to open package with identity Microsoft-Windows-Foundation-Package~31bf3856ad364e35~x86~~6.0.6001.18000 hr=0x800f0805
2009-08-10 19:33:15, Info                  CBS    SPI: Failed opening parent package Microsoft-Windows-Foundation-Package~31bf3856ad364e35~x86~~6.0.6001.18000.  hr 0x800f0805
2009-08-10 19:33:15, Error                 CBS    SPI: (CSPICbsClient::OpenPackage:227)Failed to open package with identity Microsoft-Windows-ServerCore-Package~31bf3856ad364e35~x86~~6.0.6001.18000 hr=0x800f0805
2009-08-10 19:33:15, Info                  CBS    SPI: Failed opening parent package Microsoft-Windows-ServerCore-Package~31bf3856ad364e35~x86~~6.0.6001.18000.  hr 0x800f0805
2009-08-10 19:33:15, Error                 CBS    SPI: (CSPCInstallTask::ApplicabilityScan:692)No parents for SP package found.  A release version of SP1 must be installed or scheduled for installation hr=0x800f0a05
2009-08-10 19:33:15, Info                  CBS    Session: 30022112:2758571145 finalized.  Reboot required: no
2009-08-10 19:33:15, Error                 CBS    SPI: (CSPCInstallTask::ApplicabilityScan:700)Failed to do an applicability scan of linked SP for package Windows6.0-KB955430-x86.cab hr=0x800f0a05
2009-08-10 19:33:15, Error                 CBS    SPI: (CSPInstall::CompatibilityApplicabilityScan:1056)Failed in applicability check of task hr=0x800f0a05
2009-08-10 19:33:15, Info                  CBS    SPI: Ending Compatibility\Applicability scan
2009-08-10 19:33:15, Error                 CBS    SPI: (PerformSPInstallation:764)Failed to install SP using UI hr=0x800f0a05
2009-08-10 19:33:15, Error                 CBS    SPI: (wmain:1059)Failed to perform SP installation hr=0x800f0a05
2009-08-10 19:33:15, Info                  CBS    SPI: Reporting Failed event
2009-08-10 19:33:18, Info                  CBS    SPI: SPInstall terminating, return code 0x800f0a05
2009-08-10 19:33:18, Error                 CBS    SPI: (SPIRegQueryStringValue:511)Failed to query registry value: MiscString2 er=0x2
2009-08-10 19:33:18, Error                 CBS    SPI: (CSystem::GetMachineName:348)Failed to query machine name from RAC hr=0x80070002
2009-08-10 19:33:26, Info                  CBS    SPI: Deleting directory: C:\27284f33cce7ec6bc14d809fa0813432\bab70cb91d7bad44915222.  ret=2
Anyone any suggestions?

Answer 1

Hi Gvndk,
You can try uninstalling SP1 from the command prompt:
If you cannot see the uninstall option for the Windows Vista service pack, you may still be able to uninstall the service pack at a command prompt. To do this, follow these steps:
1.
Open an elevated Command Prompt window. To do this, click Start , type command in the Start Search box, right-click CommandPrompt , and then click Run as administrator .
2.
Run the following command, as appropriate for the version of the Windows Vista service that you want to uninstall:
For Windows Vista Service Pack 1:
C:\temp\Windows6.0-KB936330-X86.exe /x:C:\temp
3.
You have to create a sandbox environment before you can continue to step 4. This helps you safely run an untrusted program. To create a sandbox, type md sandbox .
4.
To remove the Windows Vista service pack, type, or copy and paste the following command, as appropriate for the version of the Windows Vista service that you want to uninstall::
For Windows Vista Service Pack 1
start /w pkgmgr.exe /m:c:\temp\Windows6.0-KB936330-X86.cab /up /s:sandbox
5.
After Pkgmgr.exe finishes, you are prompted to restart the computer to complete the uninstall process.
If this works fine go ahead and install SP1 and then SP2 which should take care of the issue.
If not:
The only option is to Perform an inplace upgrade using the disc and then install SP1 and SP2.
Hope this helps
Regards
Anand