Having strange problems with iTunes 11? This may sound stupid - and little Windows-ish - but try a cold re-boot after installing iTunes 11 and running it for the first time.
BitPerfect is receiving all sorts of reports of erratic and seemingly
unconnected problems after installing iTunes 11. These problems seem to
go away after a hard re-boot.
My own bizarre problem actually
required me to re-boot my router! One or two strange episodes can be
viewed as a bizarre coincidence, but frankly, I've fielded about a dozen
of these today already.