Follow these steps to reset an administrator's password back to the default configuration.

In the Windows Services panel, STOP the SmarterMail service. (Find the Services panel in the Start menu's Administrative Tools option.)

Navigate to the administrators.json file. By default, this is found at C:\Program Files\SmarterTools\SmarterMail\Service\Settings\administrators.json.

Make a backup copy of the administrators.json file.

Edit the administrators.json file. Ensure you modify this filename, NOT the administrators_bak.json file. The latter is only used as a backup file in case of any potential corruption or loss to the administrators.json. SmarterMail will not recognize changes to the _bak file. (To edit the contents of the administrators.json file, right-click on the file and choose Edit or hover your mouse on Open with and select Notepad. Make sure you have administrative access when you do this.)

In this file, all system administrator accounts will be listed. Locate the entry for the administrator account you wish to reset by finding the corresponding username or display name. (The primary administrator account will also be denoted by a tag of is_primary_admin: true.)

When you've located the correct administrator account, replace the password_hash line with the following password hash. (Note that you should not simply delete the current password hash that's shown. If you do, the administrator will not be able to log in.

"1000:7Zf5bDhx+pB+3pSt9bFzbnnn9uiZi25P:+esCLUvFa/lw8c1+UMk+guGeHFfQ7Asc"

Save the file in the Settings folder using its same name. You may receive the message, "administrators.json already exists. Do you want to replace it?". Choose Yes to replace the file with the updated administrators.json.

In the Windows Services panel, START the SmarterMail service.

After completing this process, the administrator account you modified will be able to log in to SmarterMail using their username and the default password "admin" (without the quotes). That administrator should immediately go to Settings > Administrators and change their password to something more secure.