While trying to import solution to our test environment from our dev environment we got the below error
“Crm Exception: Message: Customer lookup [CustomerId] is invalid. Customer lookups can only be associated with 1 Account and 1 Contact”
The way we got it fixed
- Unzip the solution and open customizations.xml file
- Remove all attributes with name “CustomerId” (Lead, Invoice, Opportunity entity)
- Find all entity relationships with ReferencingAttributeName equals CustomerId and add to EntityRelationship new attribute: unmodified=”1″
- Zip solution back and import it.
https://community.dynamics.com/crm/f/117/t/198818
Hope it helps..
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