Even if originally trusted, an expired certificate will trigger a block.
Java blocks applications if they do not meet specific security requirements: application blocked by java security fix
The "Application Blocked by Java Security" error is a common safeguard introduced in and later to prevent malicious code from running on your computer . While it protects your system, it often blocks legitimate legacy tools, corporate applets, or educational software that lacks modern digital signatures. Why Is Your Application Blocked? Even if originally trusted, an expired certificate will