Hi Christian.
After many, many hours of googling and trying fixes, I have temporarily solved the problem. The problem lies in my registry (HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\msiserver) where if you change the key „start“ from 3 to 2′ install will work. But, if I reboot the machine I then have to change it back to 3 for installs to work.. Mystified by this.
Anyway, thanks for your help and maybe this can help someone else if they encounter the same problem.
cheers Barry