Here’s how you can migrate data with original GUIDs without use of external tools.
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Migrate data with original record GUIDs using Excel Import in Dynamics 365 CRM
Although, there are many tools/provisions which you can use to migrate data in one-go which also helps you retain or take over the original GUIDs from source instance to target instance. Let’s look at this scenario – You have a Source Environment (https://chcft166.crm.dynamics.com/ ) from which you want to move data over to the Target environment (https://cft166sales.crm.dynamics.com/ ).
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