During installation, warning pops up that the installer could not access services because of administration privileges.
APSDaemon.exe fails to start because MSVCR80.dll not found
When you open iTunes, a system error pops up saying “The program can’t start because MSVCR80.dll is missing from your computer. Try reisntalling the program to fix this problem.” when you click ok, another window pops up and it says, “iTunes was not installed correctly. Please reinstall iTunes.”
iPad and iPod are no longer recognized by iTunes
Solving the problem can be complex.
The solution involves complete uninstalling all apple software, and then reinstalling iTunes:
There is an KB Article for Removing and Installing iTunes
Go to Control Panel > Add or Remove Programs (Win XP) or Programs and Features (Later)
Use the Control Panel to uninstall iTunes and related software components in the following order and then restart your computer:
Apple Software Update
Apple Mobile Device Support
Apple Application Support (iTunes 9 or later)
Important: Uninstalling these components in a different order, or only uninstalling some of these components may have unintended affects.
Reboot, download iTunes, then reinstall, either using an account with administrative rights, or by right-clicking the downloaded installer and selecting Run as Administrator.
Do not worry, your iTunes Library will be safe unless you delete it Manually from its actual location.
Uninstalling the program does not delete your music. The Default Location for your iTunes Library on your computer is as given below unless you change it Manually:
Your iTunes library files track the media you add to iTunes, how you’ve organized it, and other information such as playlists. By default, these two files are in your iTunes folder:
Mac OS X: /Users/username/Music/iTunes/
Windows XP: C:\Documents and Settings\username\My Documents\My Music\iTunes\
Windows Vista: C:\Users\username\Music\iTunes\
Windows 7: C:\Users\username\My Music\iTunes\
Windows 8: C:\Users\username\My Music\iTunes\