Windows 10 (and 8 on which it is based) are a lot more security conscious than Windows 7: you no longer own your machine, and many, many folder will need explicit permissions to access them which the user your app is running under probably just doesn't have.
For example, all folders under "Program Files" are by default "read", "list", and "execute" enabled for all users, but are explicitly not "modify" or "write" enabled.
If you try to delete a file under "Program Files" you will get an "Access denied" exception unless your app is running with elevation.
So start by finding out what user you are executing under (again, different in Win10) and then find exactly what the path your are drying to remove is. Then check the permissions on that folder and it's parent. Almost certainly, that's your problem.
This may help:
Where should I store my data?[
^] - it's probably worth changing how your code works to use "sensible" data folders as the security we have will only get tighter, not more flexible!