> ## Documentation Index
> Fetch the complete documentation index at: https://ngrok.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Error 330

## ERR\_NGROK\_330

Domain has an invalid character sequence. Valid domains may not contain '--' in positions 3 and 4 unless the domain has a punycode prefix of 'xn--'. Failed to create an endpoint with the domain `DOMAIN`.

## Further help

If you're having trouble resolving this error, please reach out to [support@ngrok.com](mailto:support@ngrok.com?subject=Help%20with%20ERR_NGROK_330)