Hi,
Memory errors can have several causes.
call "xxx.cob"
looks strange, because usualy you call a dll file without the exention .cob
MS cobol is very old. The old ms-cobol could not handle memory more than 520k. What version do you use?
Perhaps you can cancel the modules that you don't need anymore, that should free some memory.
You can try to get more free DOS memory. On what operating system are you working?
Try to get a better compiler for your project.
Some are for free!
I hope this is helpful.