Solidworks 2014-15 resource monitor says available

I have recently upgraded Solidworks in one our University's laboratories to version 2014-15 SP5 - 32bit (Education Edition) by uninstalling the old 2012 and installing the 2014-15. The PC's that the software is installed on are DELL Optiplex 9010 running Windows 7 (32bit). The installation completed with no errors, but students using the lab are now reporting that when they do almost anything in the software, the Solidworks Resource Monitor complains that "Available open document capacity is low. Close some documents or applications to free resources.". Subsequently, they receive the message "WARNING! Solidworks is running critically low on Windows resources", and then "An error has occurred and Solidworks needs to restart ...". This happens even when the PC has been freshly restarted, no other user is logged in, and no other application or document is open!

Does anyone know what causes this issue or can suggest a remedy?

Any help is much appreciated.

Kourosh