On my mac the Addressbook application won't start anymore.
/Applications/Addressbook.App does still exist, but it seems very slim in the contents. The actual binary doesn't exist anymore in this app directory.
Surprisingly, when I open up the Applications directory in Finder, the name of the application is now 'Agenda'.
I've had this exact problem before, the remedy at that time was to get my friend (who also owns a mac) to zip the actual Addressbook application, and I simply overwrote my version.
This time my friend is not around. Although I'm not sure, but the actual files for Addressbook seem to be gone, I'd like to know if anyone knows how this can happen in the first place. Kinda creepy if you ask me.