Okay. First and foremost, thanks to all of you guys (zerojay, mara, and iball). I didn't really expect to get much help with this query. Here's where I stand right now: No additional apps running in the background. When I attempt to make a call, I get a 'unable to establish connection' error message. The internet is connected via a wifi router that is actually mounted below my desk here in the office. The amplified antenna for the router is mounted on a shelf near my desk, so there is no issue with signal strength. My settings as they currently exist are as follows: User name: <my Gizmo number> @ 'proxy01.sipphone.com Password: <my Gizmo password> Account name: Gizmo On Advanced Settings Tab/Connection Transport is set to: Auto Outgoing Proxy: proxy01.sipphone.com (I also experimented with leaving this blank) Port: 5060 Discover Public Address: <checked> Keep Alive Mechanism: Auto Keep Alive Frequency: 0 (that was the default, so I didn't change it) On Authentication Tab/Authentication Username: <blank> (this is blank now, but I also experimented with entering my username and password in the appropriate spaces on this page) Password: <blank> On STUN Tab/Auto Detect Stun: <unchecked> STUN Server: stun01.sipphone.com (I have also tried with this blank and 'Auto-Detect STUN checked) STUN Port: 3478 I apologize for the length of this post, but this is exactly how I have the account set up right now, and I have not been able to connect. If you get the opportunity, and see any flaws in the way that this is set up, please don't hesitate to let me know. I'm certain that I am not the only person who has had problems with setting this up, and hope that this might help someone (who might not have asked) to get this right as well. Thanks again, and let me know if you see anything. -Tim