# Source: https://docs.snyk.io/developer-tools/snyk-ide-plugins-and-extensions/troubleshooting-ides/authentication-using-api-token-does-not-work.md

# Authentication using API token does not work

If you **get an authentication error after you have seen the message that authentication was successful**, it may help to restrict allowed IP address families to either IPv4 or IPv6, so that requests always come from the same address during authentication.