Cannot save file error

Hello All!
I'm occasionally getting an Error:

"Cannot save file:"

with some other text about not damaging the file and saving to another temporary file.  Unfortunately it doesn't tell me why it can't save it, locked, permissions, etc.  I should mention this is a running Grails application and the file is a gsp.

Other times I hit ctrl + s and no problems.  What am I missing here?
-Steve