Windows 7: TRUST_E_NOSIGNATURE(0x800b0100) error installing SP1 for Win 7

Hi, I'm having trouble installing SP1 for Windows 7 Professional 64bit as well. I get Error: TRUST_E_NOSIGNATURE(0x800b0100)

Can you help?

I've run several MicrosoftFixit programs & tried various other solutions.

Initially it may be an idea to -

* Run the SFC /SCANNOW command.
This will check and repair if necessary any critical Windows system files.
a) Click on Start/All programs/Accessories then
b) Right click on Command Prompt option and select 'Run as administrator'.
c) At the command prompt enter: SFC /SCANNOW

SFC /SCANNOW Command - System File Checker

* Also ...
Disk Check

* Run the System Update Readiness Tool:
Description of the System Update Readiness Tool for Windows Vista, for Windows Server 2008, for Windows 7, and for Windows Server 2008 R2

* Just as a FYI > I believe the following still applies.

Free unlimited installation and compatibility support is available
for issues related to Windows 7 Service Packs:
Note: Availability of chat, phone or e-mail support differs depending on your geographic location.
Some issues may require more advanced support for which there may be a charge:

https://support.microsoft.com/oas/de...direct=1&sd=gn

I would follow JMH's suggestions first as they are easy and moderately quick

Just in passing there is both a description of the problem and a possible solution on Microsoft's technet. it is here and relevant to win 7.

Vista SP2 fails to install, error trust_e_nosignature (0x800b0100)

Microsoft is where I would go to find further info.