Error flipping to Drawing mode from Part Mode

Has anyone had this issue.
On different components, I will have both the drawing and the modelfile open. I will do some modifications on the component, and whenI switch over to the drawing, it will start to open the drawingfile and flip back to the model file. When I close out the modelfile either saving or not saving, it will show the drawing file,but when I click in the file it opens the model file again. Thishads only started happening. And it happens on random models.

Solidworks 2007 x64 edition sp 4.0
AMD Athlon 64 FX-60 Dual Core 2.73 Ghz
4 GB of RAM
Raptor SATA Drives Stripe 0
NVIDIA Quadro FX 3500SolidworksDrawings And Detailing