However I try to open any illustrator file the app crashes. Has been running smoothly for ages. Have run through suggested things like removing prefs - and have reinstalled from disk but still the same problem... HELP

(Running the latest OSX)

Look at <http://www.adobe.com/go/kb402521>

That patch didn't fix a thing with my Illy crashing problems. It's not the end all - be all for all CS3 problems.

That is a different issue.

I would simply trash the Adobe Illustrator Settings folder in the user's preferences directory first you quit Illustrator and the trash it, then restart the computer if you wish and then launch AI.

You also might have used a font that you haven't used before and that could be corrupt.

It definitely isn't happening everywhere. Could be anything, fonts, prefs, not enough space on harddisk, not enough free RAM, damaged document, damaged content, damaged fonts, bad installation. If several in your office have the problem, I would seriously start looking at fonts.