With remote attacks and no password on your Admin account, there are bots roaming the Internet between the hours of 12AM midnight and 5AM or so specifically
LOOKING for unprotected computers with no passwords. Those bots gather that list--which is quite large (thousands of computers), and send the lists to nefarious cybercriminals and hackers. At that point, they go after those computers first. Once they are in, they can do whatever they want to your computer without even breaking a sweat.
A favorite analogy I used with my Computer students is that when crooks roam the shopping mall parking lots at Christmas, they go after cars that are unlocked for obvious reasons. It takes an experienced thief 2-3 minutes to break a lock on a car door, or jimmy it, or use electronic gadgets to unlock them. It only takes 6-10 seconds for them to try a door handle and get into your car. If you were a burglar which method would you choose? Of course they look for cars that are already unlocked, and sometimes they will get lucky enough to find an unlocked car with keys left in the ignition--say goodbye to that car! It couldn't be any easier for them. By leaving your computer on the Internet 24x7x365 as most home users do these days with the advent of always-on Broadband Internet (Cable & DSL both); you will never even see it coming, as most likely you will be asleep during those late night or early morning hours! It only takes seconds to get into your computer, and steal your personal information, and if the criminal is hiding their tracks, erase your Windows or wipe everything off your hard drive so that their activity cannot be traced back to them!
Back to your Remote hacking question again. Determined hackers can still gain access to your PC even with a good password on your computer, but why bother to attack your computer with a password (like the crooks looking for unlocked cars in the Mall parking lots), when there are thousands of other computers that are already unlocked and unprotected with no password on them!
This has been proven and well documented, and when I showed students how to do this when teaching my Computer Forensics classes, they couldn't believe how easy it was.
You may not be aware of this, as few people are who don't work in the Computer Industry for a living.
Hope that answers your question.
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