blue screen when assigning AUX SENDS

[dmaxj]

I am running WIN XP with a digi 001, version 5.3.1 ProToolsLE..

I tried to assigned an AUX bus to ALL of my audio tracks at once in a session. Of course this shouldn't be a problem (I think...) I do this by holding down the ALT-key and clicking the AUX assign track above the audio fader.

After I do that - ProTools pause about 3 seconds and then sends this AWFUL, piercing noise through the digi 001 and proceeds to shut itself down.
Well, I try to reload the same session again (even after rebooting) and get the same results. So basically, my session cannot be reloaded because of the error.

Does anyone have any insight or has this happened to anyone before???

Thanks