When trying to update iTunes from 10.6.1.7 to 10.6.3, I get the message: «iTunes» has an invalid signature. It will not be installed.
When clicking OK, a second message arrives: There was detected an error during the update. If the problem doesn't solve, select Tools > Only downloads and try to download manually.
PS! The messages are translated from Norwegian and can therefore be slighty different to the original English wording.
Any suggestions to solve this will be approved!!!
You're very welcome.