Mail.app accidentally deleted (OS X 5.8) How do I restore Mail.app after it was accidentally deleted?

I have complete time machine backup of system, but can't find Mail.app in it.

I tried optional install from original disks, but Mail.app was not recognized on there -  possibly because it is out of date?

I also tried updating Mail.app on top of original Mail.app, but that failed with an error message something like:


  "Update couldn't recognize original app."
The only way to re-install applications that are on your computer is to use your Mac OS X Install DVD (if your computer is running Mac OS X Snow Leopard or below), or Internet Recovery (if you are using OS X Lion or Mountain Lion).

In your case, it's Mac OS X Leopard. This support webpage from Apple should do the trick.