Delete WINDOWS? huh, guess

Righty- this is quite possibly a virus- a friend of mine has had it. I'd check it out- better safe than sorry! Some people have reported it to be OK afetr a reboot, but yeah- just in case it's still happening.
Basically, you need to say 'yes'. the virus has just changed it to say that- and you won't actually be removing windows- but it will tell you that you have denied access. Also, it's hidden everything in the recycle bin, so it's unlikely to be empty.
Check out a program called 'MalwareBytes' (free) and 'unhack me' (paid for).
You'll need to turn the 'Show hidden files and folders' on, as the virus apparently stops showing them. Run MalwareBytes and check if it finds anything- let is remove the things it does find
With unhack me, it's software that will start before you boot up fully to the desktop, and it allows you to remove files before they are in use. When it does this, look around your recycle bin and delete what is there (look for a file called 'Dd130'. Let that complete and then let it boot up fully, then let MalwareBytes have another scan.
Hopefully this will sort things out (IF you're still getting the problem and being unable to see things in the recycle bin)
The virus causing this is likely to be a ROOTKIT virus, so is not seen by antiviruses- as they are quite new and rather malicious. Rootkits are nto like normal files, so it falls under the radar of normal viruses