Update to 10.7 did not work, cannot access iTunes. Need AVFoundationCF.dll, Ituneshelper not installed correctly, Error 7 (Windows Error 126), Error 7 (Windows Error 5)

I am running Windows 7 64 bit.

This HORROR began because I realized that my phone had suddenly lost all of the music except music that had been purchased. It also lost all purchased iBooks as well as audible books downloaded from audible and ringtones that I had purchased from iTunes.

I then thought that it would be fine once I connected to itunes on my computer. I connected to itunes and it said that there was an update available so I downloaded and installed 10.7.

I tried to run the program and got Error 7 (Windows error 5) message.

I then found several discussion questions that seemed similar to mine and I think that I tried them all. Removed everything apple and reinstalled iTunes. I followed the instructions and removed everything in the order that was listed, some I had to change security to own the file before I could delete them. I did all of the steps, (maybe I deleted too many apples items ??) emptied the recycling bin, restarted and reinstalled. I also tried the Net framework fix, used the ms fixit (the one with the picture of the man on it) and I think a few other things that I have found on this site as well as MS site. I restarted my computer every time.

The latest thing that I tried was to download 10.63 since I don't care about the new stuff. After all of this I sometimes get and message saying that I am missing AVFoundationCF.dll file and once it said something about Itunes Helper (when these two messages appear, it is separate from the error messages which occur after clicking ok on them) before getting the Error 7 (windows error 5) or else Error 7 (Windows error 126).

PLEASE HELP!