This is not the first time that updates of apple products have crashed or failed to update on PC products. Here is what I have found will work in almosyt all cases and the important thing is not to lose your playlist. The library is not that hard to reinstall but I hate to lose my playlist that I have created. Hope this helps and it is not as bad to do as it may seem:
Itune Library Problems:
If while doing an update the update fails and you get a msvcr80.dll error message then the best solution is to do a system restore to an earlier date. Go to Start-all programs - acessories - system Tools - System Restore (choose a restore date as close to the present days date as possbile)
Then reboot
Then follow the below:
If Itunes has to be removed and reinstalled:
Go to windows explorer - (Go to Start-all programs - acessories - system Tools - windows explorer)
Go to My Music
Go to Itunes
Copy the ituneslibrary.xml to desktop or file
Move ituneslibrary.itl to trash bin
Go to control panel and uninstall all apple software
Reboot machine
Go to internet and reinstall
Quicktime
Itunes
On both do a save as and put in downloads folder
Run
Quicktime
Itunes
From download folder
After itunes successfully installs
Open itunes
Go to – file-library-import playlist – find the ituneslibrary.xml file you copied previously
This will import the music and all previous playlist