Add more callers to the Authentication tab in the pcAnywhere policy.
 

• Open the Symantec Management Console click the Settings button.
• Navigate to and select the Agents / Plug-ins >  All Agents / Plug-ins.
• In the Agents / Plug-ins screen navigate on the right had side and expand Remote Management > Remote Control > Windows 
• Click on pcAnywhere Settings - Windows (Or the appropriate pcanywhere policy that is active)
• Navigate to the Authentication tab on the plugin
• Select the appropriate Authentication method from the list then click +Add button to add the appropriate users.  
• Authentication Types: 
• AD:  Validates a user or group by checking a list stored in an Active Directory Service.
• NT:  Validates a user or group by checking a workstation or user domain list.
• pcAnywhere:  Creates a caller logon account for each remote user.

Note: Only one authentication type can be used at a time.   The one that is chosen when the policy is saved is the one that will be used.   There isn't an option to use Active Directory and NT at the same time.  Also note that only one policy should be applied to a computer at a time.  If more than one policy is enabled and pointing to the same computer they will conflict and one or neither will work at a time.