What to do if your USB "Whatever" stops working, or, isn't recognised.

We have all had it happen, It worked yesterday, type of thing... USB, the ubiquidious USB 2... Often the USB mucks up and, things won't work, devices will not be "Recognised" and Nothing ya do fixes anything you are convinced that your device is wrecked, and the whole world hates you. Fear not there is a "Fix".
Ya see, often, all that happens, is the registry settings get screwed up. Even when you re-install that still doesn't fix anything. Thats because the "Settings" often remain, often multiple copies, this, just get XP confused.
Now Microsoft have had this happen too... they have indeed shown us what to do to try and fix it all, here is the link.
http://support.microsoft.com/kb/925196
Basically, ya rip out all the USB layer registry settings totally. Then ya reinstall the entire USB layer all over again.
This removes any corrupt entries and "Zeros" it so to speak, back to the, from-the-factory-default-settings. All new and shinny.
Ready to have your devices that didn't work suddenly spring into life just as it was before.
Now make sure you have any/all Drivers and Software, to reinstall, as it will be like installing the USB device for the first time..
Ok now, if all this doesn't work.. then unfortunately there is a good chance ya USB "Thingy" is beyond recovery. Oh well can't win them all.