I know its not a launch issue, but see TS1717: iTunes for Windows Vista, Windows 7, or Windows 8: Fix unexpected quits or launch issues. Does iTunes open and close successfully in iTunes' Safe Mode?
See also Troubleshooting issues with iTunes for Windows updates for general advice. A full tear down and reinstall may help.
I fixed it on my computer. Not sure which of the steps I did fixed it so I will list all of them.
I wasn't getting the error until I did the following (to prevent it from just crashing on logging into the iTunes Store)
I added C:\Program Files (x86)\Common Files\Apple\Apple Application Support; to the system variables PATH (depending on your operating system, your file path will be different). How to do that has been outlined in the above linked article.
This now caused DEP to freak out whenever I logged into the store and close iTunes. Adding iTunes to the DEP filter didn't solve the problem. So I removed all the saved system settings for iTunes and ran Apple Software Update. I also went to the DEP and added every .exe I could find in C:\Program Files (x86)\Common Files\Apple to the exceptions list (again, depending on your OS the file path may be different.)
To remove the saved system settings for iTunes you can find those in C:\Documents and Settings (for Win XP) or C:\Users (for Win 8). Find a folder named AppData or Application data under various user names and remove any Apple related files you can. I had one .log file that couldn't be deleted, but that shouldn't be a problem.