Help! Cannot uninstall SafeGuard Easy trial version.

Hi

Can anyone please help me with the following issue?

I attempted to install Sophos SafeGuard 6.00.0 Trial version and it did not appear to install - no desktop icons or "please restart your computer to complete installation" or anything else to indicate it was now on my computer. However when I restarted my computer, I could not get back in.

After one hour on the phone to technical support (ticket #3217769 if that helps anyone at Sophos!), I still wasn't able to get into my computer so I took it to a local IT geek who managed to get me back in.

I now believe he disabled MS installer as I had an error message when trying to update Skype, so I reinstalled it MS installer.

Now every time my computer starts, Sophos SafeGuard 6.00.0 is attempting to complete installation. I hit cancel.

I just downloaded Revo Uninstaller Pro to try and remove the entire program however it starts the Sophos Uninstaller program and stops on the following error message:

Error 1723. There is a problem with this Windows Installer Package. A DLL required for this install to complete could not be run. Contact your support personnel or package vendor.

Can you please advise how I can remove Sophos SafeGuard entirely from my computer?

I did contact Support however I was told: "Sophos Technical Support for Trial Edition product is only available through our website, and our online community called SophosFreeTalk : http://community.sophos.com/
We’’’’ve provided the community with information on: Installation/Un-installation, Licensing, and use of the tool. There is also peer-to-peer support from within the community where you can ask questions"

So here I am - hopefully I am in the right place! Very much a newbie with IT stuff!!

Thanks in advance :-)