The problem isn't Windows, it's how one uses it.He sent to his own metamask and by the time he checked again, it was already gone.
If he is using Windows, he probably has malware (keylogger, phishy addon, etc). so the issue is either his windows OS (I keep advising people not to use crypto on Windows), a fraudulent browser extension, phishing through hosts file or he really connected a fraud dApp. Which dApp you connected by the way?
This.I lost £2k entrusting it with my friend, he had a piece of malware on his pc that would detect a erc20 wallet in the clipboard and swap it with their own...
Wipe your drives brother
Is called crypto clipper. That mean you have a virus who detect wallet addresses by patters and manipulate your clipboard ( copy-paste ).
Try to copy a dummy wallet address and paste to a text document. See if is the same address
Op just scared the hell out of me. I have my wallets in my PC how could that happen. Should I move my wallets to a portable flash drive?