Solidworks Explorer is unacceptably slow in renaming files

I have an assembly and I need to give part numbers to about 100 components.  Each one is taking several minutes in SW explorer.  I haven't had ot do this in a long time (been back an forth w/ Pro E) and I don't remember how I used to do it, or that it was ever this painful.  Is this something new in sw2010?

I used to think Windchill was painful, but man, I just don't know what to say.  Winchill is a breeze (pun intended) compared to this painful, one file at a time, process.

Please tell me I'm doing it wrong and that there's a better way to do it.

Thanks,

BM

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