Solution: Security settings have blocked a self-signed Java application

Java applets have been around for some time and are still a part of our everyday lives. However, not everyone gets along with them.

for example, some users have been reporting getting an error message when trying to run a Java applet that states that:

This error does not appear to be related to a specific version of Windows as it is present in all versions from Windows 7 to Windows 10.

Since this problem completely blocks Java-based applications or functionality, we have decided to create a guide that will help you to avoid it with ease.

Contents index

• How can I unblock self-signed apps?
  • Make a list of exception sites
  • Set the applet’s security level to High

How can I unblock self-signed apps?

As for the causes, there are 3 main reasons why this error can appear:

• The application is not signed
  • It does not have a certificate or it is missing. Publisher name and information are locked by default.
• The user is trying to run a self-signed application from an untrusted authority
  • Self-signed certificates are also blocked by default as of the Java 7 Update
• The application jar file is missing a permission attribute
  • These are blocked because an attacker could exploit the user by running the application with a different privilege level

1. Make a list of exception sites

1. Press Windows + R
2. Write control.exe
   • This will open the Control Panel
3. Click programs
4. Click Java.
   • This will open the Java control panel
5. Go to the Security tab
6. Click Edit Site List
7. Within the Exception Site List , click the Add button
8. Paste the URL of the Java applet you are having trouble with
9. Click ok
10. Click Continue when prompted by a security warning
11. Try to open the applet again

In essence, any URL you insert into the exceptions list should now work without a hitch, regardless of what certification it may have.

2. Set the applet’s security level to High

1. Press Windows + R
2. Write control.exe
   • This will open the Control Panel
3. Click programs
4. Click Java.
   • This will open the Java control panel
5. Go to the Security tab
6. Under Security Level , toggle the High button
7. Restart the browser in which you want to run the applet.

By following any of these methods, any self-signed applet should be able to run easily in your browser. However, keep in mind that this is a workaround that should only be used when it comes to applets that you trust.

This is because you are basically disabling the security features within your PC.

If you know of another way to solve this problem, please share it in the comment section below so others can try as well.