I identified a weird problem today while troubleshooting a Timed Reset Event Monitor in a SCOM management pack. I’ll make this very brief and spare you all of the tedious details. If you are passing an ExpressionType as a parameter in a workflow, you must not include newlines and/or spaces when referencing the $Config variable.

Example: My monitor configuration includes a filter expression (for filtering within the monitor type)

Below you can see the Monitor Type with the “AndExpressionFilter” parameter defined as type: ExpressionType

Correct usage of the ExpressionType variable

The variable shown is used correctly within the Condition Detection module.

Incorrect usage of the ExpressionType Variable

In the example above you can see there exists a newline (44) and space preceding the variable (45). In my experience this caused the entire expression to be completely ignored by the workflow expression evaluator. Hopefully this helps to save you some headache.