With thanks BOAC - I've edited the value without any collateral damage

GasPath - not sure if it was coincidence but after downloading the Tweak UI, all I got was a readme file which was the same as the information shown on the main d/l site. I also picked up a little nasty called Trojan.Hiloti which by all accounts is naught piece of kit. Malware Bytes has hopefully taken care of it - fingers crossed.
Thanks again for the assistance.
SF