Update Plugin on CRM 2011 not fired when an optionset is updated from null to a valid value

Question

I have a plugin that is registered on "update", "async", "post operation". This plugin in checks for a change in the field which is an option set, and performs certain functions. This plugin works as expected whenever am updating the option set value from one value to another. But fails to even fire when i update it from null to a valid value. I mean from default (which is unassigned value) to a valid one.

Am i missing something? Or is this the expected behavior?

Answer 1

For a plugin to fire on the update of a particular field, you either have to register it to fire when any field changes, or when the particular field(s) that you're concerned about have changed. My guess is that you've specified a subset of fields to trigger the update, and your particular option set field isn't included.