How to Fix: Java 'Expired or not-yet-valid Certificate' Error

Infopackets Reader Tom G. writes:

" Dear Dennis,

I recently had to reinstall Windows, which also required reinstalling all my programs. Ever since then, whenever I try to access my work's website (which uses a Java applet), I receive an error message that says: 'Your security settings have blocked an application with an expired or not-yet-valid certificate from running.' I cannot proceed past that, and am therefore unable to access the website. The Java applet worked fine before I reinstalled Windows, so how can I get past this error? "

My response:

I had a sneaking suspicion that the website Tom was trying to access had an invalid security certificate (my guess is that it was likely expired); I asked Tom if he would like me to connect to his computer using my remote desktop support service to have a closer look. He agreed.

Tom demonstrated the website applet, and sure enough the error message: "Your security settings have blocked an application with an expired or not-yet-valid certificate from running" appeared once again.

How to Fix: Java 'Expired or not-yet-valid Certificate' Error

I also noticed that the website Tom was trying to access was using secure HTTPS (it had https://somesite.com in the URL instead of http://somesite.com) - however, the padlock which was displayed in the web browser's URL had a (!) warning next to it - meaning there was a problem with the HTTPS certificate.

By clicking on the padlock with the (!) warning, the browser reported "Connection not secure"; I then clicked to view "More information" and then on the "View certificate" page, I could clearly see that the HTTPS certificate had in fact expired some time last year. This was the reason that the Java applet was reporting an error and would not proceed.

A word of caution: normally when an invalid certificate warning is displayed in a web browser, you should steer clear of the site - especially if it's your banking website. However, in Tom's case he recalled having to go through this process before - so he was certain it was safe. In this case, I suggested adding a website exception to the Java Control Panel so Tom could continue working, even with the expired HTTPS certificate. I set that up for Tom, and he was then able to access the website.

Below I'll explain how to fix "Your security settings have blocked an application with an expired or not-yet-valid certificate from running" error step-by-step:

1. The first thing you need to do is access the Java Control Panel via the Windows Control Panel. To do so, click Start, then go to the Control Panel. Once the Control Panel window is displayed, look for the Java icon and double click it.
   
   Tip: if you don't see the Java Control Panel icon, you can also access it via the command line. To do so: click Start, then type in "cmd" (no quotes); wait for CMD.EXE or "Command Prompt" to appear in the list, then right click it and select "Run as Administrator". The command line should now appear; use your mouse to highlight the text below:
   
   c:\Program Files\Java\jre7\bin\javacpl.exe
   c:\Program Files (x86)\Java\jre7\bin\javacpl.exe
   echo this is a dummy line
   
   Right click over the above text and select "Copy". Then, go to the command prompt you just opened up, and right click in the middle of the window and select "Paste". The Java Control Panel should now be displayed.
    
2. In the "Java Control Panel" window, click the "Security" tab near the top. Near the bottom of the "Security" window, you should see a heading that says "Exception List"; click the "Edit Site List..." button. The "Exception Site List" window should now appear.
    
3. Next, go to your web browser and enter in the web address of the site that is giving you the problem. Once you've visited the site, copy the website address to your clipboard. To do so: right click over top of the web address in the browser and select "Select All"; the entire web address should now be highlighted. Right click over top of the highlighted web address text, then select "Copy" to copy it to your clipboard.
    
4. Go back to the "Java Exception Site List" window, and click the "Add" button. Then, ! IMPORTANT ! left click the empty "add" field that appears to select it, then very carefully press CTRL + V on the keyboard (make sure you only tap 'V' once!) in order to paste the entire URL into the field. If the web address doesn't appear in the "add" field, then go back to Step #3 and copy the address again. When complete, click the "OK" button, then close the Java Control Panel window.
    
5. Close your web browser and then try and access the website that previously gave you the "Your security settings have blocked an application with an expired or not-yet-valid certificate from running" error. The error should not appear any longer.

I hope that helps.

Additional 1-on-1 Support: From Dennis

If all of this is over your head or if you are stuck and otherwise need help with the "Your security settings have blocked an application with an expired or not-yet-valid certificate from running" error, I can help using my remote desktop support service. Simply send me an email briefly describing the issue and I'll get back to you as soon as I can.

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About the author: Dennis Faas is the owner and operator of Infopackets.com. With over 30 years of computing experience, Dennis' areas of expertise are a broad range and include PC hardware, Microsoft Windows, Linux, network administration, and virtualization. Dennis holds a Bachelors degree in Computer Science (1999) and has authored 6 books on the topics of MS Windows and PC Security. If you like the advice you received on this page, please up-vote / Like this page and share it with friends. For technical support inquiries, Dennis can be reached via Live chat online this site using the Zopim Chat service (currently located at the bottom left of the screen); optionally, you can contact Dennis through the website contact form.