Out of Memory (Swap device may be full)

We are getting an "Out of Memory (Swap device may be full)" error message when batch plotting. The files that include dwg's and patterns. It prints a couple of sheets,  gives the error and then kicks us out of Microstation. I noticed a post from 2007 that asked the same question but was never answered.  We have tried plotting from multiple machines and encounter the same issue. Our workstations are fairly new so I would not expect it to be a hardware issue.