When I use Openmaple with C#, if the command line involves "MapleEngine.StopMaple" or "restart", or the command line including "MapleEngine.EvalMapleStatement" is executed twice (sometimes more), it always cause a crash. Can anybody help me out with this problem? Thank you in advance!

The following is the crash report:

unhandled System.AccessViolationException
  Message=Attempted to read or write protected memory. This is often an indication that other memory is corrupt.