itunes wont open

This all sounds a bit of a muddle, I suggest you try a compete removal and installer cleanup as in the following method:

Download a fresh copy of iTunes and the stand alone version of Quicktime

http://www.apple.com/quicktime/download/win.html
http://www.apple.com/itunes/download/

Download and install Microsoft Installer cleanup utility, there are instruction on the page as well as the download. Note that what you download is the installer not the program – you have to run it to install the program

http://support.microsoft.com/kb/290301/

Now use the following method to remove iTunes and its components:
http://docs.info.apple.com/article.html?artnum=93698

If you hit a problem with one of the uninstalls don't worry, carry on with the deleting of files and folders as directed in the method.

Restart your PC.

Run the Microsoft Installer Cleanup Utility. (Start > All Programs > Windows Install Clean Up)

Remove any references you find to the programs you removed - strictly speaking you only need to worry about those programs where the uninstall failed.

restart your PC

Install the stand alone Quicktime and check that it works.

If it does, install iTunes

Just a quick check, buffer overrun can be due to incomatible codec packs, have you ever installed any of the following which are known to case trouble:
ACE & K-Lite mega codecs package, QT alternative, Storm codec
Also WinAVI

Could you do a small experiment, head for your control panel, you need classic view, and start QUicktime preferences, give any error message you get in full.

It's also worth making sure that your system is free of malware.

Having said that, when you uninstalled quicktime, did you remmeber to delete the recommended quicktime files from c:\Windows\System32 folder?

Also, sometimes QUicktime doesn't show up properly in the MS Installer cleanup utility, did you notice any blank entries or ones with just the numerbs 7.x?

That error messsage confirms it's probably not the codec issue.

If you can't install Quicktime after doing the cleanup, there are a couple of things.
Could you go to add/remove programs and find the entry for Windows Installer.
Does it say "Windows Installer 3.1 (KB893803)"? - Thats the version you should have. If you don't have it we need to sort that out first.

Could you try going through the QUicktime unsinstall and removal process again and when you get to the Microsoft installer cleanup, remove any Quicktime entries, but also look for blank entries or ones with just 7.x.

Message was edited by: polydorus

Just a quick thing I want to check. You did know that when you download the Miscrosoft Installer Ceanup Utility, you download the installer. Running the downloaded file installs it, it doesn't run the program - Nothing much apears to happen when you do this.

You run the Utility from Start>>All Programs, where hoepfully you will find it.

I am making a bit of a meal of this as I had exactly this problem with someone else.

OK, it sounds as though you are running the cleanup utility correctly.

Could you also confirm that you removed all the files and folders recommended in method for removing QUicktime, I wasn;t quite sure from your previous answer.
The sequence shoudl be
1 try using the uninstaller - but don't worry if it dosn't work.
2 delete the files and folders recommeded
3 run the cleanup.

One further bit of cleanup we haven't tried is to delete your temp folder, there are some instructions in this Apple article on trouble installing iTunes - it's towards the bottom of the page:
http://docs.info.apple.com/article.html?artnum=93976


Although there there is no Quicktime entry in the cleanup utility now, did you ever manage to remove one?
Could you also confirm if there are any blank entries or entries with just the number 7.x in them if there are they may be related to Quicktime, this can cause difficulties sometimes.



Don't worry anout the QUicktime icon on the control panel, running it was just a test to get an error message that helped with diagnosing the problem.

Since this is proving a tricky one, I will try and attract the attention of bnoir who is the most experinced with this kind of thing. Unfortunately his presence on the forum has been a bit intermittent lately.

Hmmmm. When you launch Windows CleanUp, do you see any mysterious "blank" lines in the list of programs? (They are either completely blank, or just contain a version number.)