How to Disable Microsoft Windows7/8 built-in Microsoft DTV-DVD Decoder

*Microsoft Windows7/8 built-in "Microsoft DTV-DVD Video Decoder" and "Microsoft DTV-DVD Audio Decoder", they have the highest priority, maybe override our decoder engine, so if you can't import/play/convert some special video files with Youtube Movie Maker on windows7/8, please simply disable the Microsoft DTV/DVD Decoder temporarily when running YouTube Movie Maker, then our program will use right decoder engine.     To disable the Windows7/8 built-in Microsoft DTV/DVD Decoder, it's the simplest way that just rename the Microsoft DTV/DVD Decoder files in the system32(Windows7/8 32bit) folder or syswow64(windows7/8 64bit) folder. Open Windows Explorer and navigate to "C:\Windows\system32\" or "C:\Windows\syswow64\", find the files named "msmpeg2vdec.dll" and "msmpeg2adec.dll", then rename them to "msmpeg2vdec.dll.bak" and "msmpeg2adec.dll.bak", that will disable the Microsoft DTV/DVD Decoder, and simply restore the files name can enable the Microsoft DTV/DVD Decoder again.   But if you can't directly rename the "msmpeg2vdec.dll" and "msmpeg2adec.dll" even though your account is an administrator, and get a tip like below: Just because by default only TrustedInstaller have full control permission for these files, not Administrator, so we need to assign full control permission to Administrator first, goto "My Computer -> C: -> Windows -> System32 or SysWOW64" in explorer, and find and select "msmpeg2vdec.dll", right-click the file, select "Properties". Then to the tab "Security", click on the "Advanced" button,   Then click on the "Owner" tab, now we can view the current owner is TrustedInstaller, not Administrator. So click the "Edit" button, then select "Administrators", and click "OK" button. Now you will get a tip like below: and current owner change to Administrator, click "OK" button to quit Advanced Security Setting dialog. Now we can add Full Control permission to Administrator for this file, select "Administrators" from the list of "Groups or user names", and click "Edit" button. Select "Administrators" from the list of "Groups or user names", and check "Full control -> Allow" Option, and click "OK" button.   You will get a tip like below, click "Yes" button to accept. Now, you can rename "msmpeg2vdec.dll" to "msmpeg2vdec.dll.bak" to diable "Microsoft DTV-DVD Video Decoder", then Repeat this process but for the "msmpeg2adec.dll" file. By the way, simply restore the files name can enable the "Microsoft DTV-DVD Video Decoder" and "Microsoft DTV-DVD Audio Decoder" again.