2 answers
Erin: Hi! We have a legacy workflow rule in our org that does this. The criteria is:
Rule Criteria
(Email Message: Is IncomingEQUALSTrue) AND (Case: ClosedEQUALSTrue)
and then a Field Update that sets the Status to Case Reopened.
You can translate this to a Process Builder by selecting the object of Email Message to run this on and then setting this criteria and then an Update Record option. Hope that helps!
Janet
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