Hi Pondus,
Thanks for your reply.
I downloaded and used the AVG tool and went to repair the file from the control panel, add/remove programmes and I noticed that it was Avant free software in the program list, I clicked it anyway and a message came up telling me that I was trying to use the wrong file, I looked for another Avant file and there was none listed.
At this point I decided to uninstall Avant and restart from scratch including the license file into the new installation and now all is working fine.
It appears to be something to do with trying to go straight from the trial version or maybe I just did something wrong, anyway a fresh installation of the full software seems to have done the trick.
Many thanks