MacPyMOL Users,

We have figured out why MacPyMOL was crashing for a select subset of users on start-up.  It only happens if you extract our ".tar.gz" archive using StuffIt Extractor instead of Mac OS X's built-in extraction.  The ultimate cause is rather esoteric: I had inadvertently enabled the Hide File Extension attribute on the splash screen PNG file, and StuffIt Expandor seems to have a serious bug extracting such files.

MacPyMOL should just work if you use Safari's default ".tar.gz" handling when downloading from  With Firefox, you need to make sure that StuffIt Expander is not used for ".tar.gz" files.

If all else fails, simply pop up a terminal and resort to:

tar -zxvf macpymol-0_99beta29.tar.gz


PS. Special thanks to Prof. James Berger at UC Berkeley for lending us use of his laptop for a few hours to help us to figure this all out.