[R] question about simulation.

[Lily]

I am running a 1000 simulations, it works for 2
simulations. However, I get the following error
message whenever I run it more than 3 times:

"The instruction at '0*11044080' referenced memory at
"o*3ff00000". The memory could not be "written".
and, I can also get something like "exception: access
violation (0*c0000005). Address:0*11044080".

Anybody knows what's going on? Thanks a lot!