Reinstalling iTunes

Apple iPhone - Reinstalling iTunes

I plugged in my phone today to sync with iTunes, and got an error message that "some of its required files are missing." It said I need to restore iTunes.

Easy enough but do I need to do anything before that to make sure all my information stays?

iPhone iTunes
I just reinstalled for the same reason.

Assuming you have a Windows-OS PC, a dialogue box will open asking if you want to REPAIR iTunes or UNINSTALL it. Click on "REPAIR" and let the machine do its magic.

Once it finished, I reopened iTunes and my iPhone 4 was recognized and synced flawlessly.