Clients not upgrading to 9.5

Install Log:

2010-07-26 09:08:10 Info: Logging started: installing/upgrading Sophos Anti-Virus
2010-07-26 09:08:10 Info: InstallFromPath is: C:\ProgramData\Sophos\AutoUpdate\cache\savxp\
2010-07-26 09:08:10 Info: InstallToPath is:
2010-07-26 09:08:10 Detected version of SAV has major version number: 9
2010-07-26 09:08:10 Detected version of SAV has minor version number: 0
2010-07-26 09:08:10 Info: registryInstallTo [overriding InstallToPath] is: C:\Program Files (x86)\Sophos\Sophos Anti-Virus\
2010-07-26 09:08:10 Info: SetupPlugin: updateProps.m_MajorUpdate = 1
2010-07-26 09:08:10 Info: SetupPlugin: updateProps.m_DataOnlyUpdate = 0
2010-07-26 09:08:10 Info: SetupPlugin: updateProps.m_OnAccessDriverUpdate = 1
2010-07-26 09:08:10 Info: SetupPlugin: updateProps.m_BootDriverUpdate = 0
2010-07-26 09:08:10 Info: SetupPlugin: updateProps.m_ClassFilterUpdate = 0
2010-07-26 09:08:10 Info: SetupPlugin: updateProps.m_RemoveWebScanning = 0
2010-07-26 09:08:10 Info: Installing sav only: 0
2010-07-26 09:08:10 Managed install
2010-07-26 09:08:10 Info: MSXML6 is installed
2010-07-26 09:08:10 Info: Performing major update of Sophos Anti-Virus using msi.
2010-07-26 09:08:10 Update is signalled.
2010-07-26 09:08:10 Info: Web scanning will be installed
2010-07-26 09:08:10 Info: Detected an older version of SAV, version 9. Doing a major update.
2010-07-26 09:08:13 INFO: Running Uninstall of previous version using command line: msiexec.exe /x {9ACB414D-9347-40B6-A453-5EFB2DB59DFA} REBOOT=ReallySuppress /qn UNINSTALLDRIVERS=1 UNINSTALLCLASSFILTER=0 UNINSTALLBOOTDRIVERS=0 CHECKFORSCF=0 MSIRESTARTMANAGERCONTROL=Disable INSTALLINGVERSION="9.5.0" /Lvp "C:\Windows\TEMP\Sophos Anti-Virus Uninstall log.txt"
2010-07-26 09:08:16 INFO: Finished waiting for Uninstallation of previous version. Status returned was 0l.
2010-07-26 09:08:16 Detected version of SAV has major version number: 9
2010-07-26 09:08:16 Uninstall of SAV, version = 9, succeeded but IsSAVInstalled is true (9).
2010-07-26 09:08:17 Info: Failed to rename a temp group, continuing (0x80004005)

SAV Uninstall Log:

=== Verbose logging started: 7/26/2010  9:08:13  Build type: SHIP UNICODE 5.00.7600.00  Calling process: C:\Windows\SysWOW64\msiexec.exe ===
MSI (c) (80:10) [09:08:13:810]: Resetting cached policy values
MSI (c) (80:10) [09:08:13:810]: Machine policy value 'Debug' is 0
MSI (c) (80:10) [09:08:13:810]: ******* RunEngine:
           ******* Product: {9ACB414D-9347-40B6-A453-5EFB2DB59DFA}
           ******* Action:
           ******* CommandLine: **********
MSI (c) (80:10) [09:08:13:811]: Client-side and UI is none or basic: Running entire install on the server.
MSI (c) (80:10) [09:08:16:812]: Failed to grab execution mutex. System error 258.
MSI (c) (80:10) [09:08:16:836]: Cloaking enabled.
MSI (c) (80:10) [09:08:16:836]: Attempting to enable all disabled privileges before calling Install on Server
MSI (c) (80:10) [09:08:16:845]: Incrementing counter to disable shutdown. Counter after increment: 0
MSI (c) (80:10) [09:08:16:848]: Decrementing counter to disable shutdown. If counter >= 0, shutdown will be denied.  Counter after decrement: -1
MSI (c) (80:10) [09:08:16:848]: MainEngineThread is returning 1618
=== Verbose logging stopped: 7/26/2010  9:08:16 ===

RMS Uninstall Log:

=== Verbose logging started: 7/26/2010  9:08:03  Build type: SHIP UNICODE 5.00.7600.00  Calling process: C:\Windows\TEMP\sophos_autoupdate1.dir\alupdate.exe ===
MSI (c) (18:A4) [09:08:03:671]: Resetting cached policy values
MSI (c) (18:A4) [09:08:03:671]: Machine policy value 'Debug' is 0
MSI (c) (18:A4) [09:08:03:671]: ******* RunEngine:
           ******* Product: C:\ProgramData\Sophos\AutoUpdate\cache\rms\Sophos Remote Management System.msi
           ******* Action:
           ******* CommandLine: **********
MSI (c) (18:A4) [09:08:03:672]: Client-side and UI is none or basic: Running entire install on the server.
MSI (c) (18:A4) [09:08:06:673]: Failed to grab execution mutex. System error 258.
MSI (c) (18:A4) [09:08:06:676]: Cloaking enabled.
MSI (c) (18:A4) [09:08:06:676]: Attempting to enable all disabled privileges before calling Install on Server
MSI (c) (18:A4) [09:08:06:676]: Incrementing counter to disable shutdown. Counter after increment: 0
MSI (c) (18:A4) [09:08:06:678]: Decrementing counter to disable shutdown. If counter >= 0, shutdown will be denied.  Counter after decrement: -1
MSI (c) (18:A4) [09:08:06:679]: MainEngineThread is returning 1618
=== Verbose logging stopped: 7/26/2010  9:08:06 ===

RMS Install Log:

Install from:[C:\ProgramData\Sophos\AutoUpdate\cache\rms]
Install to  :[(null)]
MsiPackagePath: [C:\ProgramData\Sophos\AutoUpdate\cache\rms\Sophos Remote Management System.msi].
RMS: Current product is installed.
RMS: Upgrade requested; Checking RMS Build version.
RMS: Build Number: Old=1835, New=2013.
RMS: Setup Plugin running MsiInstallProduct(C:\ProgramData\Sophos\AutoUpdate\cache\rms\Sophos Remote Management System.msi,
                                            REINSTALLMODE=vmuso SOPHOS_TP_TOKEN=1 REINSTALL=ALL REBOOT=ReallySuppress TRANSFORMS=1033.mst)
!RMS: Setup Plugin failed to install product: Exit code [1618]