Have you tried putting the workspace in?
We set up all our dashboard under "Default" workspace. Using just your first line with "Default" and I'm still getting the same error. (I saw in another thread someone using Nothing or GUID.empty for the default which is why I tried that.)
Please post your code, could be something else causing the error.
The id of the default workspace is the same as Guid.Empty ('00000000-0000-0000-0000-000000000000') , so that would work.
You can use:
New Guid()
Guid.Empty
Nothing
they all do the same thing in vb. If you are still getting the null pointer error, then its something else in your code.
Its helpful to use null coalescence in cases where unexpected nulls may cause the null pointer error, "Object not set to a reference of an object", to happen
