In the recent round of end-of-year Maintenance Release (R#) Updates for QuickBooks Desktop products, a common ingredient has been the incorporation of additional changes to the already implemented and increased security restrictions Intuit has imposed for User Management requiring Administrators of QuickBooks Desktop files to either log-into or secure Intuit Accounts. In the most recent updates:

Admin users are now able to edit the user ID while signing into the Intuit account within QuickBooks Desktop.
Admin users can now create a request for access (RFA) for the Secondary Admin (Intuit account) role.
Users can send Request for Access (RFA) to the master admin to become part of the company file Intuit account when signing in to the company file or by signing into My Company.
All of these are designed to expand the pre-existing changes to QuickBooks Desktop security incorporated into the past several version maintenance-release (R#) updates in which an Intuit account became mandated for QuickBooks Desktop Company-files and Users in the following situations:

When an existing QuickBooks Desktop Company file is opened using the Admin credentials, and no Intuit account is associated with the file, the QuickBooks user will be prompted to log in or create an Intuit account. (Pro and Premier Administrators may currently elect to delay this action for up to 28 days and QuickBooks Enterprise Administrators may currently elect to delay this action for up to 42 days.) It is likely that the number of days in which an Administrator may elect to delay the action of linking their Company tile to their Intuit account will be reduced over time.
When a new QuickBooks Company file is created.
For QuickBooks Desktop users with the following connected services: Payments, Payroll direct deposit, TSheets time tracking, Payroll Workforce, Receipt Management (which was new in QuickBooks 2021), as well as Mobile Warehouse and Inventory services for QuickBooks Enterprise Solutions. In the future, it is likely that many cloud-based connected-services will require users to have Intuit Accounts so that those services can be liked/associated with a specific QuickBooks Desktop file.
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