Provider drops the call

SIP/prov... is circuit-busy

-- SIP/prov... is circuit-busy
== Everyone is busy/congested at this time (1:0/1/0)

Make sure:

1. You are properly registered to the Provider
2. You are sending correct Destination Number Format
3. You are sending correct CallerID Number Format
4. Using correct codecs

Provider blocked your IP

This could happen after several failed registrations. Cause of this could be wrong password.

Also make sure you are not using weird characters in the password to register to the Provider, like / \ and @

Incorrect number format

If Provider returns something like:

-- Got SIP response 503 "Service Unavailable" back from xxx.xxx.xxx.xxx

Try to add '00' (if Provider is in Europe) or '001' (if Provider is in USA) to Provider Rules to destination.

Some Providers wants numbers with international prefixes.

Codec mismatch

Check codecs for your server and your provider. Often there are not matching and call is not possible.

Provider has no available lines to service the call

503 "Service unavailable: no more gws" back from xxx.xxx.xxx.xxx - Provider does not have more open lines to serve your calls.

See also

• I cannot make a call
• I have a problem with Calls
• SIP/2.0 503 Service Unavailable