I have a requirement that when the case owner is changed from queue to user need to updated all related task owner with case owner. How can I achieve it using process builder. I am not able to get the reference to Queue id from process builder. Do anyone have any idea to solve it out.
If I understand it correctly, your problem is that you cannot set the criteria for your process to fire when the case owner is changed from a queue to a user?
Since the Record ID Prefix for Queues is "00G", you could define the criteria for your action group to:
You can then add that the new OwnerId needs to start with "005" (since it needs to be a user), and then add an action to update all related tasks.