Key Not Valid for Use in Specified State won't GO AWAY

I really need help as I've got no iTunes, iTunes files, or Apple files AFTER following HT 1923 and then by following BY HT 1926 I also followed "Troubleshooting issues with iTunes for Windows updates".

I've also tried to download iTunes versions: 11.3.1 10.7 10,6,3 10.3.1 ALL COME UP WITH : Key Not Valid for Use in Specified State

.

THIS IS THE 3rd iTunes UPDATE for Windows that I've had installation problems with - before that there was NEVER a problem when the 'new update is available' box showed up, I just clicked it and all worked perfectly

I have used System Restore but that hasn't worked either. There are no Apple programs in Control Panel>All Programs OR in File Explorer which I've

clicked BOTH 32 AND 64 bit Program Files Folders.

I did a live chat with Norton once and they asked if they could fix that problem I had at the time with one of their issues 'remotely' and it did fix it .

I think this problem needs a 'remote' fix -- does anyone know if Apple Support offers that service?? Also I couldn't fine out on the Support page what

the going rate is for a phone tech call.

BUT I am willing to try any 'FIX' that you can come up with and will report back as to what happened.

Windows 8.1 all updated

Dell desktop

Internet Explorer 11.0.9600.17232 Update Version: 11.0.11 With 'install new versions automatically' box checked

IPS Comcast with their Norton Security Suite and Firewall (NOT using Windows Firewall)

1 dog that's tired of me cussing

1 wife who says "can't you fix that???!!! 🙂

ALL help IS greatly APPRECIATED Patrick