Users cannot be deleted from CRM, instead user records are disabled.
To remove access to CRM from a user, either disable the user record or remove all security roles from the user.
When disabling a user, check the following items for knock-on effects:
- Saved views, does the user own any views that are shared? An administrator does not have access to personal saved views. If on-premise you can search for these in the database otherwise you will have to login as the user to see the views.
- Ownership, do any records need to be reassigned. This depends very much on how record ownership is organised. If records are owned by teams then there is nothing to do. If not, then some records may need to be reassigned but probably not all (especially activities).
- Workflows, does the user own any workflows or other processes? Change ownership to an account that is user independent (for example, CRM Admin).
- Reports. Review SSRS for any reports created by the user.
- Licence. For CRM On-line, unassign the user's licence in Microsoft Office 365.
- Email. If using the E-mail Router, re-run the Email Router Configuration Manager, test settings and Publish.