Problems running signed applet in Vista and IE7
Posted by Van Glass on 15 November 2007 12:13 AM
On a Windows OS other than Windows Vista, when running a signed applet, a user is prompted with a security warning dialog box and must respond. If "Yes" is clicked, the applet will have AllPermissions to run on the user's machine. This includes permission to write/delete a file from the local disk.|
On a Windows Vista OS, this is no longer true. Instead, AllPermissions is limited to Java Applet scope, not Windows scope. Because a process running in IE has a low integrity level, it will not be able to write/delete a file from a medium/high integrity level directory.
For this reason when a user running IE7 on Windows Vista with Protected Mode enabled the user may receive an error indicating that the applet cannot load or perform certain functions due to insufficient administrator rights. This is a known bug in the current Java Plugin distributed by Sun Microsystems for Windows Vista and is discussed in more detail here:
Note that this issue only occurs in IE7 and not other browsers such as Firefox. Sun Microsystems is currently working to develop a new version of the Java Plugin that runs completely outside the process context of the IE7 browser to avoid this issue. Please see the link provided above for availability on this version, or visit http://java.sun.com/getjava/ to download and install the latest version of the Java Plugin.
To workaround this issue you may disable Protected Mode in IE7 as follows:
1. Launch Internet Explorer 7 in Windows Vista.
2. Click Tools, then click Internet Options.
3. Click the Security tab.
4. Disable Protected Mode.
5. Click OK.
6. Restart Internet Explorer.