If you understand a little bit how registry works you can try out to remove java root keys in registry. I have automated this java root key remove process in Java Destroy post.
If you do not like playing with registry at all, then just download and install Total Uninstall.
Total Uninstall works similar like add/remove programs. Let's take a closer look.
Open Total Uninstall. Look for java and click Uninstall button.
Select "Uninstall analyzed program" and pres "Launch"
You can skip this part:
Are you sure you want to uninstall this product?
This part will use original uninstaller.If you try it already, click "No":
The final dialog came out. Click "Uninstall".
This will delete all java registry keys
And finally - Finisho!
Repeat this steps for all installed java versions. In another words - it is a huge possibility when you uninstall one of version then the other ones is already damaged. You have to get all java versions away from computer. If java is removed, it will apears in color gray:
Now you can visit java download page to install brand new java.
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