Hello !

You may read a correct path to Acrobat reader from Windows registry,
substitute a %1 by the name of the file and then
run it by:

RUN /N command_line , where
command_line is like string like 'C:\ACROREAD\ACROREAD.EXE MYFILE.PDF'

If you need to know how to read it, I can send you a code : 'cos it takes a some place

Good luck