I got a computer from my grandparents, and after cleaning it out, I find these folders in the root directory of my C: drive. Its about 700 megabytes total. Warning: Spoilers inside! All of which have MRT.exe inside. From what I've read, it is Microsoft's malicious removal tool, which would make sense seeing all the adware on it when I received it. I was wondering if I would be able to delete these folders without repercussion, or if deleting it will cause an issue.