Usually the error means the source file you use is not compatible with Ulead. Sometimes it will be fixed by installing the update packs.
If the update packs do not help, you will need to use some third party tool to transcode the source file to some format Ulead can use.
BTW, what's the properties of the source file you want to use in DVDMF??
Hope this helps.
H.T.
Ted (H.T.)
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