"Save as" of part/assembly parent not allowed when child assembly open

I have been having a problem with SolidWorks 2010 ever since it was installed late last year.

Namely, every time I try to save as a part or assembly that are used in another assembly which is open nothing happens. i.e. I click on the icon and nothing happens, no error message, just nothing.  The icon is not grayed out either.

Now through experimentation, I have found that if I close the assembly that uses the other part or assembly, I can now use the save as command.

Is there some obscure switch or tag I have to hit to activate this or disable whatever is preventing this?  I have reset the options to factory default with no result.

Or do I simply need to reinstall SolidWorks?

By the way I am using Solidworks Premium 2010 SP5.0

Thanks for any answers,

Roy Martin

SolidworksAssemblies