Configuring the Sametime client refers to making sure that all
phone numbers are in E.164 format and setting the preferred device
(Setting your geographic location). Make sure all phone numbers are
in E.164 format.
Procedure
Go to File > Preferences > Voice and Video > Preferred Numbers to change your
phone numbers.
Set your Geographic Location. Go
to File > Preferences > Voice and Video > Routing Calls so that your preferred device does not switch back
to Computer, which will prevent you from being able to make calls
via Application Enablement Services.