What is Pro Tools Aggregate?

[sixstrings22]

i see it's been 'discussed to death' but I have never seen or heard of "Pro Tools Aggregate" ever before -until today. I installed PT 9.02 a few weeks ago on my IMAC /10.6.8 and everything has been smooth. I then did all the same upgrades to laptop and finally decided to do some mixing on the laptop and there's no normal outputs. Core audio engines doesn't recognize the 003? The output path shows this wierd symbol and no 003 symbol etc.
been there/done that? give me hand then, if ya can.

laptop is 2.33GHz/2 gig ram /10.6.8

[sixstrings22]

actually I don't want to know. After (re)installing the drivers - ...I looked around here and found one thread - w/ an answer:
Setup> etc.

rebooted.
maybe someday I'll need to know, but now we're rollin again.

thanks.