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Delivery Status & Reports
An invalid number error means VoltFax could not recognize or connect to the destination fax number.
Common Causes
- Incorrect fax number
- Missing area code
- Missing country code for international faxes
- Extra digits or formatting errors
- Disconnected or inactive fax number
Troubleshooting
Before resending:
- Verify the recipient’s fax number.
- Include the correct country code when sending internationally.
- Remove unnecessary spaces or special characters if required.
- Confirm that the destination number is capable of receiving faxes.
Correcting the fax number often resolves this error immediately.
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