> ## 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 121

## ERR\_NGROK\_121

Your `PRODUCT` version "`VERSION`" is too old. The minimum supported agent version for your account is "`MINVERSION`". Update to a newer version with 'ngrok update', by downloading from [https://ngrok.com/download](https://ngrok.com/download), or by updating your SDK version. Paid accounts are currently excluded from minimum agent version requirements. To begin handling traffic immediately without updating your agent, upgrade to a paid plan: [https://dashboard.ngrok.com/billing/choose-a-plan](https://dashboard.ngrok.com/billing/choose-a-plan).

## 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_121)