Dial Prefix Invalid

What Causes This Error

The configured dial_prefix or force_dial_prefix is causing all outbound calls to fail. The combined prefix + phone number produces a dial string that Asterisk or the carrier rejects. Common causes include double-prefix (both VICIdial and dialplan adding prefix), prefix with special characters, or prefix that conflicts with dialplan pattern matching.

How to Fix It

• 1 Check current dial prefix in campaign: Admin > Campaigns > dial_prefix

• Enable Asterisk debug to see actual dial string: asterisk -rx ‘core set verbose 10’

• 3 Watch for ‘Dialing’ log entries to see what string is being sent to carrier

• 4 Compare actual dial string to expected format required by carrier

• 5 Check for double-prefix in dialplan: cat /etc/asterisk/extensions.conf | grep -A5 outbound-context

• 6 Test with a known-good number format directly from Asterisk console

• 7 Remove prefix from campaign if dialplan handles it: set dial_prefix to blank

How to Prevent It

Test dial string format on every new campaign before running production traffic. Document expected dial string format for each carrier. Review dialplan and VICIdial prefix configuration together to prevent double-prefix scenarios.

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