PDMWeb Viewer Error in View Tab

When selecting a drawing in the web-based SolidWorks Workgroup PDM Viewer (2012), I receive the attached error on some machines (seems to happen on Win7 and Win8).  I've tried the clean uninstall and reinstall of the eDrawings but can't seem to make this error go away.

Thanks in advance for any assistance,

Rusty

SolidworksWorkgroup Pdm