jstart.exe is not starting.

Dear All,

I am trying to start the portal server.But jstart.exe processes are not starting.

I have checked in developer trace. I am getting this error.

ERROR => SfCreateDynShm: ShmCreate(80, 75804672, CREATE) failed (rc = 4 SHM segment already exists) [jsfxxshm.c   2235]

ERROR => SfEInternalError: SfCInstanceManager::createDynShm: SfCreateDynShm failed (rc = 5 object already exists)  [sfxxinst.hpp 644]

LOG => Instance state is "Not started" (STARTING @ 0, INACTIVE).

MPI: dynamic quotas disabled.

MPI init: pipes=4000 buffers=1279 reserved=383 quota=10%

F 

F  ********************************************************************************

F  *** ERROR => Failed to create the dynamic shared memory segment.

F  ***

F  *** Please see section 'Shared memory issues'

F  *** in SAP Note 1316652 for additional information and trouble shooting advice.

Please give a solution for this.

Thanks.