I received a report from a user today that he repeatedly got the message "Unable to complete call as dialed" when dialing a local number. After a number of attempts, he tried using his cell phone and got a busy signal. I took a look at the trace file and it appears to me that the H.323 gateway released the connection with a cause of 'User busy'. However, why would CallManager deliver the 'Unable to dial' message instead of a busy signal?
Well, is the h323 gateway the only gateway (or RG member) in your Route List? Have you by chance modified the CM service parameter that controls whether the CUCM will continue routing on "user busy". If there are other route groups (RG) in the route list AND you have the CM service configured to continue routing on "user busy", then you could be punting the call to another gateway unknowingly.
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