Apple iTunes 8 Won’t Play Video - April 13, 2009
I recently upgraded to iTunes 8 and all my music videos stopped playing in iTunes. Some files would produce a message “This computer is not authorized to play ’song’. Would you like to authorize it?” Authorizing the computer does not help–it just asks you to authorize over and over. Some music videos would play audio but not play video. Here is how I fixed it:
1) Quit iTunes
2) Move this file to your desktop: /Users/YOURNAME/Library/Preferences/ByHost/com.apple.iTunes.nnnnnn.plist
3) Restart iTunes
Note that you need to replace “YOURNAME” with the name of your user account. Also, you will have various letters and numbers replacing the nnnnn part of the file name above.
If it works, you can delete the file you copied to your desktop. If it doesn’t work, you might want to put it back where you got it.