Consistent Problem Changing File References

When I am changing the reference of a drawing file to point to a new model or assembly, I find that SW 2010 frequently screws up and won't let me do it.  It gives me the error message:

Invalid Operation: Cannot change file type (e.g. from Part to Assembly)

This usually occurs when I'm trying to change a drawing reference from one assembly to another assembly (I'm not stupid enough to try to change a ref of a part to an assembly as the error msg indicates) and when it does I must reboot my entire computer to get SW to unscramble it's brain and allow the CLEARLY LEGAL operation to go forward.

It just happened when I tried to change the reference from one part to another part.  It's beginning to seriously damage my productivity as I must perform this operation 15 - 20 times every day.  That's a hell of a lot of reboots...

I'm curious if anyone else has seen this problem and if anyone has a workaround I could use.  I would consider the SP2.1 upgrade were it not for the horror stories I'm hearing about.  Perhaps SP4 or 5 will finally be stable?

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