Those two symptoms taken in conjunction suggest that you've got a damaged Apple Application Support, tera.
Let's try something relatively simple first. Go into your Uninstall a program control panel, select Apple Application Support and click "repair".
Does that clear up the messages?
If not, could you let us know if you've got a 32-bit or 64-bit version of Windows, please? (That makes a difference as to what we'd have to try next.)
You probably have remnants of prior iTunes installation that needs to be unistalled.
To to your Control Panel and remove all Apple programs - sort by Publisher:
uninstall: Bonjour, Quicktime, iTunes, Apple Application Support, Apple Mobile Service Device, Apple Software Update
Restart your PC
Go to Apple - iTunes and download (if you are running Windows 64 bit - look for the link in the text for the link for the proper iTunes installation
This should give you a clean installation.
I am using Windows 7, 32-bit:
I have the same problem. I managed to solve the matter by downloading:
Microsoft Visual C++ 2005 Service Pack 1 Redistributable Package ATL Security Update
After that, Open Control Panel, Uninstall Program.
Then, select iTunes.
Hope you are successful!
This solution is based on this hint - http://answers.microsoft.com/en-us/windows/forum/windows_vista-windows_programs/ microsoftvc80crtversion80507274053typewin32publick/c1359ee5-e18d-4512-8bff-89093 6db2810,
Following the instruction toI install http://www.microsoft.com/downloads/en/details.aspx?familyid=766a6af7-ec73-40ff-b 072-9112bab119c2&displaylang=en#filelist