Success! All fixes together in one thread...step-by-step...
1.) Make sure you have the file "mapi32.dll" version 1.0.2536 in your /windows/system32 folder.
How do I check:
Click on you Start Menu in the lower left
Then click on "My Computer"
Then click on the "Windows" folder
Then click on the "system32" folder
Scroll to the "m"'s and put your mouse pointer over the "mapi32.dll" file, the version should pop up.
If you don't have this file there are some creative ways to get the file that people have posted on this support forum. Look into those ways.
2.) Make sure ALL of the following are "started": TCP/IP NetBIOS Helper, Windows Management Instrument, and WMI Performance Adapter.
How do I do this:
Click on the Start Menu
Move your mouse pointer to "My Computer", but don't click on it
RIGHT-click on "My Computer" and then choose "manage" in that menu
In the left hand panel double-click "Services and Applications", then double click "services" in the right panel.
Find those three files in the windows and click on them and make sure it says "Started" and "Automatic" next to the names.
3.) Download and install the stand alone Quicktime 7.0.2 player. You need this for iTunes to run. Here's the link:
http://www.apple.com/quicktime/download/standalone.html
Restart your computer.
4.) Download Bonjour for Windows from this link:
http://www.apple.com/support/downloads/bonjourforwindows_readme.html
NOTE: Before you start the install do the following(VERY IMPORTANT) DISABLE ALL YOUR ANTIVIRUS AND SPYWARE SOFTWARE. If you're running Norton 2005 right click on the system tray icon and click "disable Norton internet security" and "disable antivirus auto protect" make sure you do it until at least the "next system startup". I was also running Avast Antivirus so I had to "stop on-access protection". Those were the ones on my system, your system may be different.
Then run the Bonjour install and restart your computer.
4.) Download the iTunes install program from here:
http://www.apple.com/itunes/
ONCE AGAIN (VERY IMPORTANT) DISABLE ALL YOUR ANTIVIRUS AND ANTISPYWARE AS YOU DID FOR THE PREVIOUS STEP!!!!
Restart your computer when it's done.
This should work. For me, all the songs and playlists updated except for like 4 songs which said they couldn't be found. But when it asked if I would like to find the file I clicked "yes" and it lead me directly to the folder that had the song in it and when I clicked on the file the song started to play. I now had v5.0
I really hope this helps.