look at this thread to give you an idea of what that means...
http://12.199.124.105/index.cfm%3Fpage=topic&topicID=34403 and here's how to set it up...
To increase type "heapsize += 10000000" where 10000000 is the amount of bytes to increase by. You can't decrease, reloading 3dsmax will set the assigned memory to default. Don't increase the memory too much, I think default is about 7.5meg or 20meg(can't remember to be honest), try increasing it by 10 meg at a time and importing the file. You could add the heapsize command to a startup script so you always have more memory for scripting purposes, but this leaves less memory for actually working in max.
Edited by ally on Aug 3, 2011 at 04:45 AM