the vertixes and cells in my model are over 10,000,000 ,so i should enlarge the corresponding parameters. but when i try to change the maxcel over 10,000,000 the system show the error message"COULD NOT ALLOCATE MEMORY TO INCREASE PARAMETER MAXCEL TO 10000000", this parameter is just about 8,000,000. how can i make this parameter larger? and the same to maxsc2. and other parameters.

Are you running a 32bit machine or 64 because you are getting very close to how big a model a 32 bit machine will take? How much memory do you have in your system? Finally, you can make better use of whatever memory you have by presizing the param file using prosize rather than resizing it within pro-STAR afterwards.

my pc is 64bit,i setup the model in pro-star directly, i think the command MEMORY and it's prameters are determined by the software not by my pc.

Do you have a Windows PC or Linux? There is no 64bit Windows version of STAR yet so on Windows, you can't go past 32bits. If you have Linux, how much memory do you have on the machine, how much swap space and are you sure you loaded the 64bit linux version of STAR?