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- Field names are NOT updated in Visualforce Email Templates if they are more than one relationship away. Eg I had MyCustomObject__r.Campaign__r.WorkshopName__c - this didn't get updated.
- This breaks Process Builder and FLOWS! Big time. And you only get a version ID in the Flow error message. From here https://success.salesforce.com/ideaView?id=08730000000DlBIAA0 this is a great tip. Also see Process Builder Errors and Weirdness.
"Go to Workbench > Info > Metadata Types & Components > then choose 'Flow' from the dropdown > click Expand All. Then do a browser Find to search for your ID." (This was a process that updated a record that made another process action, and the ID was in the flow error message from the first process).
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Also check any other integrations you have!
This is a fabulously detailed post from Johan (@simplysfdc) on this topic http://www.simplysfdc.com/2016/09/salesforce-rename-field-name_4.html
Now to clean up this mess.
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