Something disappeared from my computer -- MSVCR80.dll

Hello madrive7,

Thank you for the details of the issue you are experiencing with installing the latest iTunes update. I recommend following the steps below:

Resolution

Follow these steps to resolve the issue:

Check for .dll files

1. Go to C:\Program Files (x86)\iTunes and C:\Program Files\iTunes and look for .dll files.
2. If you find QTMovie.DLL, or any other .dll files, move them to the desktop.
3. Reboot your computer.
   Note: Depending on your operating system, you may only have one of the listed paths.

Uninstall and reinstall iTunes

1. Uninstall iTunes and all of its related components.
2. Reboot your computer. If you can't uninstall a piece of Apple software, try using the Microsoft Program Install and Uninstall Utility.
3. Re-download and reinstall iTunes 11.1.4.

I understand that you have already uninstalled iTunes, but when you get to this step, it is important to uninstall iTunes and the related components in the order listed in the link for that step.

You can find the full article here:

iTunes 11.1.4 for Windows: Unable to install or open

http://support.apple.com/kb/TS5376

Thank you for using Apple Support Communities.

Best,

Sheila M.

This did not solve my problem. Problem continues.....

This issue has resurfaced again with a brand new Windows 10 install.

Problem –

iTunes (x64) install fails on Windows 10 with following error:

Fix –

Install the following windows libraries and the reinstall iTunes. Brand new install of Win10 does not come with these dlls/libraries. I had to
find and install them manually (Refer to your the "removed apps" utility/webpage on your desktop if you are refreshing/upgrading to win10).

For those that don't have the utility you refer to, installing the Microsoft Visual C++ 2005 Service Pack 1 Redistributable Package MFC Security Update before attempting to install iTunes should help.

See Troubleshooting issues with iTunes for Windows updates for further help if required.

tt2