Minecraft is not working it says access denied?

I'm using a windows pc and minecraft says access denied I'm doing this for my friend it's been a year now please hel

If youre trying to log into your account you may be typing the wrong password. Click on the forgot password thing and set up a new one then try logging in.

Sounds like the user doesn't have permission to run some files, right click the launcher and run as administrator. The anti-virus may also be blocking some files.