Rick says his XP machine got bit by malware, and the utility he used to fix it was also malware. Leo says that it may not be, but modern malware attaches itself to critical system files, causing the drivers to disappear and lose internet connectivity. It's likely the malware utility didn't even fix it and more malware is being installed without his knowledge.
The only real safe way to solve the issue is to back up his data, format the hard drive, and reinstall Windows from a known, good source. Then he should update it until there's no critical updates remaining to install. It's the only way to be sure he has gotten all of the malware off his system.
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