Q: I accidentally uninstalled Bonjour and now I can't get itunes. It's recommended that I uninstall itunes and then reinstall it. If I do this will it erase the music I've already downloaded?

Under normal circumstances, an uninstall/reinstall doesn't touch your content. (That being said, it's still always a good idea to maintain a current backup at all times in case of disasters of any sort.)

Uninstalling and then reinstalling your iTunes should also get your Bonjour reinstalled.

For the reinstall, use an installer downloaded from the Apple website:

http://www.apple.com/itunes/download/

If you'd prefer not to uninstall iTunes, try the following procedure.

Download and save a copy of the iTunesSetup.exe (or iTunes64setup.exe) installer file to your hard drive:

http://www.apple.com/itunes/download/

Download and install the free trial version of WinRAR:

http://www.rarlab.com/

Right-click the iTunesSetup.exe (or iTunes64setup.exe), and select "Extract to iTunesSetup" (or "Extract to iTunes64Setup"). WinRAR will expand the contents of the file into a folder called "iTunesSetup" (or "iTunes64Setup").

Go into the folder and doubleclick the Bonjour.msi (or Bonjour64.msi) to do a standalone Bonjour install.