Mouse scroll wheel doesn't

Windows XP Professional SP2.

The mouse has an irritating problem. Whereas all the mouse buttons work,
the scroll wheel won't do anything untill I go into control panel, change
the scroll behaviour, change it back and click OK. It now works, but if the
machine is turned off, or put in standby or hibernated, the scroll wheel
stops working again until the above is repeated.

Any ideas? Anyone?


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