You can modify a user's properties and role membership in ArcGIS Server Manager. If your users are stored in an LDAP server or Active Directory, you will need to use that product's user management tool to modify user properties.
If a user account was used to register the ArcGIS Web Adaptor with your site, and you later change the account's password or demoted the user to a role that does not have administrative privileges, you need to reconfigure the Web Adaptor. Even though HTTP communication is not disrupted between the Web Adaptor and the site after modifying the account, the Web Adaptor cannot update its internal list of machines until you reconfigure. For full instructions, see Configuring the Web Adaptor after installation.
To modify a user in Manager, follow the steps below.
- Open Manager and log in as the primary site administrator or a user with administrative access. If you need help with this step, see Logging in to Manager.
- Click Security > Users.
- Locate the user you want to modify and click the edit
icon corresponding to that user. This opens a dialog box that allows you to edit the user's password, email, full name, and description. - To change the user's role membership, click the add role
icon to add roles from the Available roles list. Click the Delete icon 
next to a role to remove it from the Member of list. - Click Save to apply your changes or Cancel to abandon the changes and return to the Users page.