Quicktime 7.69.80.9 fails to start on Win 7, uninstall did not work

Question

iTunes updated and now my QT pro will not load.  I get the following error message:
Faulting application name: QuickTimePlayer.exe, version: 7.69.80.9, time stamp: 0x4cf444ff
Faulting module name: QuickTimePlayer.dll, version: 7.69.80.9, time stamp: 0x4cf444e1
Exception code: 0xc0000409
Fault offset: 0x00005b6d
Faulting process id: 0x51c
Faulting application start time: 0x01cc579f2534c7a4
Faulting application path: C:\Program Files (x86)\QuickTime\QuickTimePlayer.exe
Faulting module path: C:\Program Files (x86)\QuickTime\QuickTimePlayer.dll
Report Id: 66e17596-c392-11e0-852a-68b599ece3fe
I uninstalled QT, did a reboot, removed all QT files including any in /window/SysWOW64.  Then I reloaded a stand alone version of QT while I was not connected to a network with my Norton Firewall off. 
Still no luck.  Then I removed all Appe software from the machine and reloaded just QT.  Still nothing.
What am I missing?

Answer 1

Interesting. The pref file issues have more commonly produced a sort of error-message-free launch failure (except that a button for the Player shows in the Task Bar). But the symptoms of this sort of thing tend to be subject to change without notice (which is why I thought I'd better check).
The pref files can be difficult to track down. (Where they show up on a Vista or 7 box seems to depend on whether or not you're 64-bit, or possibly even depending on which versions of QuickTime have been installed on the machine. haven't quite worked out the rules for that yet.) But the following instructions are worth a try.
First we need to check some View Settings. Log back into your usual account.
In your Start menu, open Computer.
In your Organise menu, select Folder Options.
In the View tab, make sure that "Show hidden files and folders" is selected, and Hide extensions for known file types is unchecked.
Click OK.
In Computer, open Local Disk C:\ or whichever drive your user documents are stored on.
Open the "Users" folder.
Open the folder with the name of the Windows User account in which the QuickTime Player isn't displaying properly.
Open the "AppData" folder.
Now the hunt for the QuickTime preferences begins.
Open the "Roaming" folder.
Open the "Apple Computer" folder.
Do you see a "QuickTime" folder in there? If so, drag that out onto the Desktop. Now try launching the QuickTime Player. Does it open properly this time?
If there was no QuickTime folder in \Roaming\Apple Computer\, or if the Player still doesn't open properly
Quit the QuickTime Player taskbar button again.
Go back into the "AppData" folder.
Open the "Local" folder.
Open the "Apple Computer" folder.
Do you see a "QuickTime" folder in there? If so, drag that out onto the Desktop. Now try launching the QuickTime Player again.
If there was no QuickTime folder in \Local\Apple Computer\, or if the menu has not been cleared
Quit the QuickTime Player taskbar button again.
Go back into the "AppData" folder.
Open the "LocalLow" folder.
Open the "Apple Computer" folder.
Do you see a "QuickTime" folder in there? If so, drag that out onto the Desktop. Now try launching the QuickTime Player again. Any luck this time?