So I was using the following link to try to permanently disable ads on Skype for Windows 7:
http://www.youtube.com/watch?v=8jTbnFpeoPc
What had happend was, I went to C:/Windows/System32/drivers/etc and located the "hosts" file. I opened that same file in Notepad and added an extra line that says the following.
# Block Skype ads
0.0.0.0 rad.msn.com
When I tried to save it, I changed the save as type type from "Text document" to "All files", and save it under the same name and file type as the file I'm intending to replace. When that is done I click save and a dialog box asks me if I want to replace the existing file under the same name and file type, and when I click "Yes" another dialog box comes up and says that access was denied.
Please help me find a solution to this problem. Thank you very much.