This will happen if AutoInsert Notification has been turned off. You would
need to turn that back on.

http://zachd.com/pss/pss.html#autoplay
covers this from the XP point of view - Vista is likely about the same, but
I haven't tried that.

--
Speaking for myself only.
See http://zachd.com/pss/pss.html for some helpful WMP info.
This posting is provided "AS IS" with no warranties, and confers no rights.
--

"ionixuk" <ionixuk@discussions.microsoft.com> wrote in message
news:62E80860-43C8-4BC1-A4A8-C4138D46C9BC@microsoft.com...
> Anyone else have an issue where, if you have MEdia Player or Media Center
> open and you eject the disk, neither program then recognises the next disk
> you put in? If I close Media Player / Center first, then eject, then put
> one
> back in, it's all hunky dorey...