Before attempting to delete an Active Directory user account, consider the following steps:

1. Verify if the account is active or inactive.
2. Verify if the account still outstanding tasks associated with it.
3. Verify if you have the proper permissions to delete the account.
4. Verify if the user’s credentials still exist in any other systems, and if so, delete them.
5. Verify if any mailboxes and other resources are still associated with the user account, and if so, detach them.
6. Ensure that all needed information, such as data and files, is retained securely, if necessary.
7. Ensure that all backups of the user account have been disabled, if applicable.
8. Finally, delete the account.