It is possible for your Java installation to become corrupted. This can lead to several problems.
Symptoms
"illegal URL redirect" - This message can appear after an Applet fails to load.The error began after installing Java 1.7.0_09. In the Java Console you may see a stack trace that begins with:
java.lang.SecurityException: illegal URL redirect
at com.sun.deploy.net.HttpUtils.followRedirects(Unknown Source)
To fix this problem, clear your Java cache. (See instructions below.)
How to Clear the Java Cache
Note that this is different than clearing your browser cache.
On Windows 7 you can:
- Launch the Java Control Panel,
- click "General" tab,
- under "Temporary Internet Files" click "Settings",
- click "Delete Files",
- select only "Cached Applications and Applets" and hit OK.
It took almost a minute to clear my Java cache.