"Read Only" files left over after SW crash

When SW crashes and i have a part/assembly open it leaves the ~\$ file in the part folder. When I open that part back up it says the part is "Read Only" and I can't edit it. This requires me to close out, delete the ~\$ file, then open the part back up. Sometimes the ~\$ doesn't let that part show up on a drawing or in the BOM for the assembly.

Is there any way to prevent this from happening?

Has anyone else experienced this?

specs:

Windows 7 32bit

SW 2011 sp4

SolidworksGeneral