# 13247: Dial: Invalid From number (caller ID)

Log Type: APPLICATION

Log Level: ERROR

## Description

You attempted to initiate an outbound phone call or message, but the `From` parameter you supplied was not a valid phone number or alphanumeric sender ID.

Twilio accepts phone numbers in [E.164 format](/docs/glossary/what-e164) (i.e. "+1 format"), 10-digit US and Canadian numbers with any combination of non-digit separators, or Alphanumeric Sender IDs (SMS only) with up to 11 alphanumeric characters \[a-zA-Z0-9]. Refer to [this page](https://support.twilio.com/hc/en-us/articles/223133867-Using-Alphanumeric-Sender-ID-with-Messaging-Services) for acceptable characters.

The number must not be on a do-not-originate (DNO) list, and Alpha Sender IDs may not be generic.

### Possible causes

* You have supplied a phone number that was not in [E.164 format](/docs/glossary/what-e164)
* Your `From` phone number is on a do-not-originate (DNO) list

### Possible solutions

* Ensure your number is formatted in [E.164 format](/docs/glossary/what-e164)
* Ensure that your `From` number is assigned and not on a do-not-originate (DNO) list.