A good friend told me yesterday that he's been trying to get BT out to fix his router. Unfortunately he was phoned on the weekend by some scammers who claimed they were from BT and he allowed them remote access to his laptop and they downloaded some software. At the point that they asked him to log on to his internet banking he hung up and uninstalled the software.
I urged him to update and run Malwarebytes and SuperAntiSpyware as well as his Avast antivirus.
He's told me that he ran the MalwareBytes scan and it didn't find anything but it then asked him to update it. He did, then it asked him to reboot. He did and upon restart it is asked him for the admin password, he put it in but now can't get it to safe mode or to progress in to windows at all.
Update - I burnt and ran the DVD and tried the 'diagnose' option but this didn't help.
I'm now at the stage of resetting (but keeping the personal files) but I get the blue screen and the text of:
Reset this PC
You need to sign in as an administrator to continue but there aren't any administrator accounts on this PC
There is an option of clicking 'Forgotten your password or can't see your account'