Hi Senthil, The best way it will be upgrade because all your data will be upgraded without any additional operations. You can build separate enviroment import organization to it upgrade. Export database in CRM 4.0 version on import it to CRM 4.0 production.
If you want to play with data migration you can do in several ways: - import export by CSVs - 3rd party tool like Scribe - write own application to migrate data from one CRM to another - use Biztalk I strongly suggest upgrade because this is easiest and simplest
solution. KG
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