You should not run wallet on Windows. Period. LTC wallet of a friend of mine was robbed by a trojan horse he did not even know he had. Despite having antivirus installed.
Google litecoin wallet trojan windows.
Your friend's problem wasn't windows itself, but downloading and running random files from the interwebz while naively relying on a virus scanner.
Pull your heads out of your asses. No piece of software, be it OS or antivirus, will be able to protect you from yourself.
agree on that. but be honest, it's not only warez that has trojans attached, many pages/mails have these too.
How may times you just ignored ssl certificate warning and just clicked on a link ? don't say never.