Getting 'java.net.UnknownHostException' error while activating in Katalon Studio

Last updated: September 2025

Getting java.net.UnknownHostException error while activating in Katalon Studio.

You might encounter this error message when your private network restricts some Katalon's domains.

1. If you are behind a private network, please configure Proxy for Authentication or whitelist Katalon's domains.
2. You can also identify which domain to whitelist in the error log. Navigate to Help > Error log.In the error log below, the domains encountered with UnknownHostException error must be whitelisted.