I have a dreadful problem with Itunes which I am unable to sort out.
Something went wrong with the latest update and for some reason my pc does not recognise Itunes!!! I've tried downloading the updates again but this fails.
I've now tried deleting Itunes from my pc but for some reason it won't go. When I check the programme files on the C drive Itunes is not there, but when I check the Add/Remove programmes Itunes is still there and I can't remove it, I get a message saying it is a network resource that is unavailable. I also get a message to look in the C drive/documents&settings/ the path then leads onto Apple updates. Two things then happen, firstly I can't find the path and secondly Apple updates are not there, presumably I've deleted it!
I've decided not to bother with updates anymore unless they are critical , too many problems in the past . As missspeedy says a system restore should sort it
Further to the earlier answers, I too have had problems with updating iTunes and I don't bother any more. I could never notice any changes. I found that it was the Quicktime add on that caused most of the problems and the way I got around it was to uninstall both iTunes and quickTime before upgrading. As I've said , it is never worth the bother anyway and 'if it ain't broke don't fix it'.
In Vista go to start , maintenance , backup & restore centre then 'use system restore to fix problems & undo changes to windows' it will give you a recommended restore point which will probably be the date you did the update . Just click next & finish .
It will take a few minutes & your computer will reboot . If that doesn't work try the same process & an earlier date .
In XP it's start , all programs , accessories, system tools , system restore