I think it may have something to do with your default web browser.
"The QuickTime installer will automatically detect your browser's plugins folder and install the plugin." -
http://plugindoc.mozdev.org/windows.html
That said, if Firefox isn't your default browser, QT may have missed it in the install.
So, all you should have to do is make Firefox your default browser and reinstall QT.
Heres how to set it to default:
"Open Firefox and go to "Tools -> Options ->General -> Default Browser -> "Check Now" (or "Edit -> Preferences -> Navigator -> Set Default Browser" on Mozilla). If that doesn't work, try the following:
In Windows XP, go to "Start -> Control Panel -> Add/Remove Programs -> Set Program Access and Defaults (on the left) -> Custom". After expanding the "Custom" category, you will see Internet Explorer and other installed browsers listed under "Choose a default Web browser". Select Mozilla or Mozilla Firefox.
If that doesn't work,
In Windows Control Panel and if Windows XP is using the Control Panel "Classic View":
Click on "Folder Options -> File Types".
In Windows XP using the Control Panel "Category View":
Click on "Performance and Maintenance". Then, click on "File Types" in the left column under the heading "See Also".
Assign the following filetypes to the browser you wish to set as default:
URL:HyperText Transfer Protocol
URL:HyperText Transfer Protocol with Privacy
URL:File Transfer Protocol
HTML File
HTM File (optional)
Note that you may find the URL file types above under extension "N/A" or "(none)". "
http://kb.mozillazine.org/Setting_Yo...lf_the_default
If firefox is already your default browser, let me know and we'll go from there.
--Aric