Connection problems

SSL Certificate Error: PKIX Path Building Failed

What the log looks like

sun\.security\.provider\.certpath\.SunCertPathBuilderException: unable to find valid certification path to requested target
javax\.net\.ssl\.SSLHandshakeException:.*PKIX path building failed

How to fix it

  1. Update your Java installation to the latest release of Adoptium Temurin (Java 17 or Java 21) so it includes up-to-date root security certificates.
  2. Check your computer's date, time, and time zone settings in your OS preferences and sync them automatically, as an incorrect clock makes valid SSL certificates appear expired.
  3. Temporarily disable 'HTTPS Scanning', 'Encrypted Web Scan', or 'SSL Inspection' in third-party antivirus software (such as Kaspersky, Avast, Bitdefender, or ESET), which replaces website certificates with untrusted local ones.
  4. Disable any active VPNs, proxies, or network-filtering apps (like Qustodio, Covenant Eyes, or AdGuard) and retry the login or installer.
  5. If you are installing Fabric on Windows, download and run the official Fabric '.exe' installer instead of the '.jar' version, or install Fabric directly through a third-party launcher like Prism Launcher.
LoadersVanilla, Forge, Neoforge, Fabric, Quilt, Server
SeverityBreaks something
CategoryConnection problems

Check your own log

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