Genrally the command would not be
mcc -m folder\file.m
because your file is in folder2, NOT folder, according to you. So you should have folder 2 be the current folder and then say
mcc -m file.m -a *.* -a ../folder1 -a ../folder3
This should include all the files in the current folder (folder2), then all the files in folder1 and folder3. I use the .. to go up a level to the parent folder where all 3 folders reside. You used a single dot which meant that folder1 was a subfolder of the current folder, and if you were in folder2 (where your .m file is), that would give the file not found error because folder1 is not a subfolder of folder2.
