I have completely uninstalled an old version of XAMPP and installed the new version 1.7.
Apache is OK - but MySQL is already "ticked". If I click "start" I get:
ERROR: MySQL service not started [-1]
If I try to untick MySQL (uninstall service), there is no effect.
This is fully patched Vista.
** update **
That problem is fixed - I think I must have installed MySQL as a service in the older version. have now uninstalled it as a service, and it now starts & stops OK