"the application requires an Xtra (Quick time 3) that either dose not exist or failed to initialize properly. Please make sure the appropriate Xtras are in the Xtras folder(s)"
The following steps were used for my specific situation, but if missing an Xtra file is keeping you from playing media some derivation of this could work for you....
1.download shockwave V10 from the following
http://sdc.shockwave.com/shockwave/download/download.cgi?
2. Locate and download the Xtra file called QT3Assets.X32 I found it in public space located at
http://college.hmco.com/chemistry/shared/install_xtra.html
(or find your own QT3Asset.X32, note QT6Asset.X32 worked also)
3. Finally copy and paste QT3Assets into the following file C:\WINDOWS\system32\Macromed\Shockwave 10\Xtras
(if your system is not structured like this then look for an Xtra folder under shockwave and copy and paste the file there.)
Anyway after doing those 3 steps the media is working and the error message is gone.
ciao
jrw5

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