Is this SAS/IML 14.1? Did you recently install 9.4? Is this on a new machine? Is it on Windows?
My guess is that perhaps the MEMSIZE system option was set for the older version of SAS, but has not been set for the 9.4 version. (Or the older system was Linux and the new system is Windows.)
See the article "Large matrices in SAS/IML 14.1" for instructions about how to set the MEMSIZE system option so that SAS can use enough RAM to allocate your matrices.