Keyboard entering nonsense, "save as" not closing
Gateway, Windows XP
Recently, I've had some kind of keyboard problem that's making Word, Outlook, and Putty completely unusable.
For Outlook/Word, the "Save As" window pops up every second and immediately pops up again if I try to cancel. I have to press any key on the keyboard before it will cancel, and it doesn't stay canceled for long.
When I'm using Putty, I get endless repetitions of "4~" or "^[[4~". Backspace usually just sets it off again, and del always does. When using pico, I'm constantly getting "unknown command" messages. It starts/stops this when I try to type something but also without me doing anything.
In Photoshop, my images keep reverting.
When this problem is in effect, my backspace/delete/arrow keys often don't keep going when I hold them down, as well. When they do, it's very slow. This is the only symptom in Firefox and Notepad, which otherwise work fine.
This problem comes and goes without cause and varies in how bad it affects my computer.
How is the "Save As" window even possible? There's no key-combination for "Save As", just "Save" (this document has already been saved before). It's also odd that I have no apparent problems in Firefox...