Hello,<BR><BR>I&#039;ve written a module that makes several large calculations that takes about 5 till 10 seconds. During that time it must be forbidden for other clients to call the module because off mixing data. I have done this by setting booleans (blnLock = True/False) at the beginning and the end off the module. This is effective but very bad for the performance if you are in the queu.<BR><BR>Is there a better way to do the trick?<BR><BR>With regards,<BR><BR>Jan.<BR>