Got a strange one for you, its got me stumped. Client has an HP laptop, running Windows XP. Client can use the system normally for a period of time, and then the system starts behaving like the shift key is stuck. Caps Lock Off = upper case letters. Caps Lok On = lower case letters. In either case, can't type numbers, get the special symbols instead.
Okay, fine, so replace the keyboard, right? Done that. No effect. Rebooting the computer, or shutting it off entirely, returns the system to normal operations. Then after another couple of hours its doing the same thing again.
Client primarily uses Microsoft Word, but I have verified that the problem is present in Wordpad as well, so its not just an Office issue. Client has reported that the period of time that the system is useable after a reboot has been decreasing steadily. A few months ago it happened once or twice a day. Now its after less than an hour.
Any ideas? Obviously replacing the computer is a last resort.