ASP.Net is the wrong platform to use when scheduling tasks because of the way the web works. The code is not running until someone visits the page, then the server runs the code for the page, sends the html back to the client and then disconnects and waits indefinitely for someone else to request a page.
You could certainly take the code and put it into an exe and then schedule that. However, since you already have the code in a webpage your fastest way to schedule this is to probably create a batch file that loads the webpage on the server and then schedule that.
See
windows - How can I open a URL on a schedule in the default browser? - Super User[
^] for examples on how to run a webpage. Essentially you put start or explorer and then the url. Pretty simple.