3.5 |best|: Zoiper

: Features a built-in contact list that can integrate with local address books (like Outlook or Mac Contacts) for quick dialing.

Zoiper 3.5 Pro licenses are locked to the email address used at purchase. You cannot transfer them. If you lost your key, Zoiper support will not re-issue keys for v3.5 (they will offer you a v6 discount). zoiper 3.5

, typically found in the installation folder for the Free version or %APPDATA%\Zoiper for the Biz version. 2. Key Configuration Metrics Configuration in 3.5 is managed through "Sections" within the zoiper.conf General Settings : Controls basic behavior such as (Biz only), Audio Options : Features a built-in contact list that can

: Usually NAT-related; often fixed by enabling RPort or disabling STUN. 407 (Proxy Auth Required) Audio Options : Usually NAT-related