How to Repair Java Installationby Jim Campbell
The Java compiler is freely distributed by Sun Systems. If your Java installation is corrupt, uninstalling and reinstalling the software fixes any corrupted or deleted files that cause issues when you try to run Java-enabled websites. Some newer Java websites require the latest Java compiler version, so this process also fixes any compatibility issues with older Java compilers trying to run new Java websites.
Click the Windows "Start" button and select "Control Panel." Click "Uninstall Program" in the Program section of the Control Panel. Click the "Java" icon in the list of programs. Click "Uninstall" to remove the software from your system.
Open a Web browser, and navigate to Java's website. Click the "Free Java Download" button on the homepage to download the latest version of the Java compiler. When the window opens to save the file, save it to "C:\temp" directory to quickly find it when you run the install files.
Click the Windows "Start" button again and select "Computer." Double-click the "C" drive, and double-click "Temp," which is the location of the install files you downloaded in Step 2.
Double-click the "setup.exe" file to start the installation. Click "Install" on the opening welcome window. Java installs on your computer. Click "Close" on the Success screen to close the installer wizard. Reboot the computer.