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Run this SQL script to login in any NAV 2013 Database (ex: After Restore)

delete from [dbo].[User]

delete from [dbo].[Access Control]

delete from [dbo].[User Property]

    delete from [dbo].[Page Data Personalization]

delete from [dbo].[User Default Style Sheet]

delete from [dbo].[User Metadata]

delete from [dbo].[User Personalization]