Visual Studio 2010 Service Pack 1 is not installing

While installing Visual Studio 2010 Service Pack 1, I am getting this error:

Installation did not succeed. Microsoft Visual Studio 2010 Service Pack 1 has not been installed because:
Generic Trust Failure.

How can I install Service Pack 1? I am using Windows 7 32 bit.

Here is the log file:

OS Version = 6.1.7600, Platform 2
OS Description = Windows 7 - x86 Enterprise Edition
CommandLine = "D:\Softwares\Programming\Visual Studio 10 Service Pack 1\Setup.exe"
Using Simultaneous Download and Install mechanism
Operation: Installing
Package Name = Microsoft Visual Studio 2010 Service Pack 1
Package Version = 10.0.40219
User Experience Data Collection Policy: UserControlled
Number of applicable items: 22
Summary Information:

SetupUtility
Service Pack 1 Package
Microsoft Team Foundation Server 2010 Object Model - ENU
Microsoft Visual Studio 2010 Performance Collection Tools - ENU
Microsoft Visual Studio 2010 Ultimate - ENU
Microsoft Visual Studio 2010 ADO.NET Entity Framework Tools
Dotfuscator Software Services - Community Edition
Microsoft SQL Server Data-tier Application Framework 1.1
Microsoft SQL Server 2008 R2 Data-Tier Application Project
Microsoft SQL Server 2008 R2 Transact-SQL Language Service
Microsoft SQL Server 2008 R2 Management Objects
Microsoft SQL Server System CLR Types
Microsoft F# Redist 2.0
VSTO 4.0 Runtime x86
Visual Studio Tools for Office
Help Viewer v1.1
Microsoft SharePoint Developer Tools
Microsoft Visual C++ 2010 x86 Runtime - 10.0.40219
Microsoft Visual C++ Compilers 2010 Standard x86 - 10.0.40219
NDP40-KB2468871.exe

Possible transient lock. WinVerifyTrust failed with error: 2148204800
Possible transient lock. WinVerifyTrust failed with error: 2148204800
D:\Softwares\Programming\Visual Studio 10 Service Pack 1\VS10sp1-KB983509-Pro.msp -
Signature verification for file VS10sp1-KB983509-Pro.msp
(D:\Softwares\Programming\Visual Studio 10 Service Pack 1\VS10sp1-KB983509-Pro.msp)
failed with error 0x800b0100 (No signature was present in the subject.)
No FileHash provided. Cannot perform FileHash verification for VS10sp1-KB983509-Pro.msp

File VS10sp1-KB983509-Pro.msp (D:\Softwares\Programming\Visual Studio 10 Service Pack
1\VS10sp1-KB983509-Pro.msp), failed authentication. (Error = -2146762496). It is
recommended that you delete this file and retry setup again.

 Exe (D:\Softwares\Programming\Visual Studio 10 Service Pack 1\SetupUtility.exe)
 succeeded.
 Exe Log File: dd_SetupUtility.txt
 MSI (D:\Softwares\Programming\Visual Studio 10 Service Pack 1\VS10sp1_x86.msi)
 Installation succeeded. Msi Log: Microsoft Visual Studio 2010 Service Pack
 1_20120208_111135435-MSI_VS10sp1_x86.msi.txt
 Final Result: Installation failed with error code: (0x800B010B), "Generic trust failure. " (Elapsed time: 0 00:01:59).

This is the kind of error that can usually be fixed by the System Update Readiness Tool. Give it a shot and see if it solves it.