Problems after quicktime update

Question

I had been putting off installing an update to quicktime cause it normally does me no good to update... but I went away from my normal ways and did it. Now something is wrong.
I updated my quicktime... then my iTunes stopped working... Then I uninstall iTunes, then try to install the newest download on apple.com... It gets to the part with quicktime and has some error and falls out... So i go to uninstall quicktime and i get some fatal error... Now i can see im going to have fun with this, so I get quicktime off by manually going into regedit, and using a microsoft cleaning program, and a registry degrag program that cleaned up all the itunes and quicktime fragments hanging in memory.... after that I go ahead and install the iTunes + quicktime.... everything goes great... yea sure lets go ahead and open it once install is completed... NOPE "Itunes has encountered a problem please tell Microsoft about this" dialog box opens.
Whats next? I removed all programs, cleaned up fragmented registry files, did a clean and new install downloaded minutes ago, installs, but it just wont boot up, the computer has been restarted already so whats next?
I have done this clean install and go around and screw with quicktime files and manually deleting them EACH time i try a reinstall because this program just wont leave.
My goal is to have iTunes back... any suggestions?

Answer 1

Okay. That rules out one complication if you didn't previously have one of those installed. (With some versions of them, "QuickTime" componentry is installed on the PC which can interfere with an upgrade to a higher version of QuickTime proper.
So let's try completely scraping out the existing iTunes and QuickTime, and then doing a careful staged reinstall of the two programs.
*Preliminary phase*
Download and save copies of the standalone QuickTime installer and the iTunes installer bundle to the PC. (Don't install them just yet.)
Latest iTunes Installer
Latest Quicktime Installers … get the one that doesn’t mention iTunes
Download and install the Windows Installer CleanUp utility. (We'll be using it during the uninstall phase of proceedings.)
Description of the Windows Installer CleanUp Utility
*Uninstall Phase*
Switch off antivirus and antispyware software prior to any uninstalls. Attempt to uninstall both iTunes and QuickTime from Add/Remove Programs.
1) *If Add/remove doesn't let you remove a program:* Use the Windows Installer CleanUp utility to remove the installation configuration information for the program. (Launch CleanUp, find the entry for the program in the list of programs displayed in cleanup, select that entry and then click "Remove".)
2) *Even if Add/Remove lets you remove one of the programs:* Run CleanUp anyway, and look for any leftover installation configuration information for the program. If you find any, remove it with CleanUp.
Next, we'll try removing any leftover program files and folders (if present).
For QuickTime:
1. On the Start menu, click My Computer (or double-click My Computer on the Desktop).
2. In My Computer, open Local Disk.
3. Open Program Files.
4. Right-click on the QuickTime folder and click Delete from the shortcut menu.
5. Navigate to C:\Windows\system32\.
6. Remove the files QuickTime.qts and QuicktimeVR.qtx. (If “Hide filename extensions for known file types” is enabled on the PC, then those two files will appear as “QuickTime” and QuickTimeVR”.)
For iTunes:
2. In My Computer, open Local Disk.
3. Open Program Files.
4. Right-click on the iTunes folder and click Delete from the shortcut menu.
Now, restart the PC.
*Reinstall phase*
Switch off antivirus and antispyware applications prior to the install.
Start the QuickTime install by doubleclicking the QuickTimeInstaller.exe file you downloaded earlier. Once that completes, restart the PC.
Start the iTunes install by doubleclicking the iTunesSetup.exe you downloaded earlier. Once that completes, restart the PC.
Now try launching iTunes again. Does it launch properly this time?