[Ham-Computers] Windows XP Home Edition Mouse problem?

[KD7JYK DM09]

A friend recently told me that several times a day, her mouse pointer will
disappear from the screen, then re-appear about five seconds later.  It
happened once or twice a year before, now it's several times a day.

Moving the mouse does not bring it back, it just shows up on it's own.

What would cause such a problem?

Thanks,

Kurt