It looks that I have a virus, I had norton before but never updated it. I just bought a new one and unistalled the old one before installing the new one; while doing this it was taking too long, after about 15 minutes I cancelled it and tried to install again, but it says: "another installer is currently running. Please wait for it to complete and try again"
About 4 hours have passed and I have rebooted about five times and still the same, please help me!

Norton provides a tool to uninstall NAV here: Norton Removal Tool. This often takes care of the problem so you can get the program to install correctly. I have used it twice with good results.

If the above does not work a great guy by the name of Dave Taylor has detailed instructions on how to totally remove NAV so you can do a clean install of it. Remember it is critical to follow the instructions to the letter. Here is a link to the correct page of his site: "Ask Dave Taylor! Tech Support Blog.

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