I don't think I can explain why you get the error. make itself has told you why you got the error ("can't find generic.mak") and I can't think of any way to explain "can't find generic.mak" without actually saying "can't find generic.mak".

So either generic.mak isn't on your computer, or make is looking in the wrong place.

%1 is the first parameter. So for the command "dir *.txt /s", dir would see *.txt as %1 and /s as %2.

If generic.mak is in \yyyy then probably you need to set DVD_MAKE=\yyyy.
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