simulation problem or bug

Dear All, I am trying to run simulations starting from the msf file (nm 7.1). I've done it multiple times for the current project without any problems. BUT for one specific problem, I see a very strange behavior: The simulation script runs just fine with SUBPROBLEMS=0 option, but fails with any other value (including 1) with the following error: 0MULTIPLE SUB_PROBLEMS IS INCOMPATIBLE WITH OTHER INFORMATION IN THE CONTROL STREAM AND INPUT MSF I am not sure whether it is important but the original run completed with 134 (rounding error) estimation error and successful covariance step (with UNCONDITIONAL option) Any ideas of what is the problem? Thanks! Leonid -- -------------------------------------- Leonid Gibiansky, Ph.D. President, QuantPharm LLC web: www.quantpharm.com e-mail: LGibiansky at quantpharm.com tel: (301) 767 5566