Obtain the serial number of a DTU

Via Device Manager

The serial number of a DTU should normally be displayed in the 'Device instance path' of the properties window in Device Manager. It should look something like this:

USB\VID_056A&PID_0336\5AZQS00085

Via Wintab

Using Wintab the serial number can be obtained from the device context.

For example, in the ScribbleDemo code-sample add the following call to the beginning of the OpenTabletContexts function.
 

char uniqueTabletID[32] = { 0 };
int numBytes = gpWTInfoA(WTI_DEVICES, DVC_PNPID, uniqueTabletID);

 
This populates uniqueTabletID with the serial number of device 0.
If there are multiple Wacom devices on the system (or the user preferences have information for multiple devices, having had different ones plugged in in the past), then it may be necessary to get the serial number of device 1, or device 2, etc.
This can be done as follows:
 

int deviceNumber = 0; // Place device number here
char uniqueTabletID[32] = { 0 };
int numBytes = gpWTInfoA(WTI_DEVICES + deviceNumber, DVC_PNPID, uniqueTabletID);

It can always be guaranteed that the DTU-1141 attached to a system is device 0 if only the DTU-1141 is attached to the system, no other Wacom devices.
Alternatively it can be achieved by either of the following:

1. • Clear user preferences (this is destructive and will remove user settings)
   • Stop the Wacom Professional Service
   • Remove contents of C:\Users[USERNAME]\AppData\Roaming\WTablet
   • Start Wacom Professional Service
      

2. Execute the following command at a command prompt:

C:\Program Files\Tablet\Wacom\PrefUtil.exe /remove-all

NB: in older driver versions, PrefUtil.exe is located in C:\Program Files\Tablet\Wacom\32\PrefUtil.exe

Please note that the service takes a few seconds to fully start up, depending on the machine.