Resharper 7.1.3 installation error

So I need the latest resharper because I stupidly installed VS2012 Update 2, which broker test runner.

I downloaded 7.1.3 installer (ReSharperSetup.7.1.3000.2254.msi) but it fails to run with the following Windows Installer error:

The system administrator has set policies to prevent this installation

I turned on windows installer logging and I get the following log:

=== Verbose logging started: 07/06/2013  11:13:36  Build type: SHIP UNICODE 5.00.7601.00  Calling process: C:\Windows\System32\msiexec.exe ===
MSI (c) (58:08) [11:13:36:821]: Font created.  Charset: Req=0, Ret=0, Font: Req=MS Shell Dlg, Ret=MS Shell Dlg

MSI (c) (58:08) [11:13:36:821]: Font created.  Charset: Req=0, Ret=0, Font: Req=MS Shell Dlg, Ret=MS Shell Dlg

MSI (c) (58:30) [11:13:36:831]: Resetting cached policy values
MSI (c) (58:30) [11:13:36:831]: Machine policy value 'Debug' is 0
MSI (c) (58:30) [11:13:36:831]: ******* RunEngine:
           ******* Product: C:\Users\redto\Downloads\ReSharperSetup.7.1.3000.2254.msi
           ******* Action:
           ******* CommandLine: **********
MSI (c) (58:30) [11:13:36:832]: Machine policy value 'DisableUserInstalls' is 0
MSI (c) (58:30) [11:13:36:879]: SOFTWARE RESTRICTION POLICY: Verifying package --> 'C:\Users\redto\Downloads\ReSharperSetup.7.1.3000.2254.msi' against software restriction policy
MSI (c) (58:30) [11:13:36:879]: Note: 1: 2263 2:  DigitalSignature 3: -2147286775
MSI (c) (58:30) [11:13:36:879]: The installation of C:\Users\redto\Downloads\ReSharperSetup.7.1.3000.2254.msi is not permitted due to an error in software restriction policy processing. The object cannot be trusted.

MSI (c) (58:30) [11:13:36:880]: Note: 1: 1718 2: C:\Users\redto\Downloads\ReSharperSetup.7.1.3000.2254.msi
MSI (c) (58:30) [11:13:36:880]: MainEngineThread is returning 1625
=== Verbose logging stopped: 07/06/2013  11:13:36 ===

I am running Windows Server 2008R2.

I have tried modifying my local group policies for Windows Installer to no avail.

Many thanks for any help.