Applies To:
  • CitectSCADA 4.20 Service Pack D, 5.xx

Citect is hanging and therefore I cannot get a Drwtsn32.log to get debugging information for Citect Support. Is there anything else I can do to obtain debug information? 

A new debugging feature introduced to Citect makes it possible to obtain debug information even if Citect is hanging. This feature incorporates a Watchdog thread which detects if the main thread is hung. When it does detect a hang the watchdog generates raises a breakpoint exception which is then logged in Drwtsn32.log. The information in log will tell us where Citect has hung. This feature is included with Compiler and Runtime. The parameters covering this feature are as follows.


Enables a watchdog thread that will detect if Citect is hung and then generate a hardcoded debug event so that the exception handler is run and debug information is recorded. This should only be enabled when instructed to by Citect Support

Allowable Values
0 Disabled
1 Enabled
Default 0 (Disabled)


When the watchdog is enabled this controls the time (in seconds) between watchdog polls.

Allowable Values
1 to 60 Seconds
Default Value 5


When the watchdog is enabled this controls the number of times the watchdog retries its poll before deciding that Citect has hung

Allowable Values
1 to 10 Retries
Default Value 3

Note:    Enabling the watchdog may cause Citect to crash during normal operation-especially on startup or shutdown-depending on the WatchdogTime and WatchdogRetries settings. The watchdog should be disabled after the needed logs are created.

See KB Article Q3588 if you are using Citect 5.41 or higher.