Windows 7: USB Mouse & KB not functioning in Win 7

Hi,
I'm hoping that somebody can help me.
My Win 7 Pro boots OK but the USB mouse and keyboard will not function from that point. This occurred after a recent update. The m&kb work in BIOS and under boot from DVD
I've followed the recovery instructions but;
1/ PS3 m&kb also do not work
2/ Repair finds corrupt files but is unable to fix them (even after 5 reruns)
3/ None of the System Recovery files will work
4/ Repair Installation cannot be processed because there is no input method available from the startup screen.
5/Malwarebytes found and removed 3 items when run from another disc, but still no Win 7.
6/I've loaded a separate SSD with Win 7 and it works fine, so I can get access to the drive and this would indicate that there are no hardware problems.

I can get the data from the old disc, but there are several programs on it that are difficult to replace so I would much prefer to fix the old drive.
Any suggestions?