There are many task schedulers for ASP.NET. Two of the more famous ones are Quartz.NET and Hangfire. Both of these are amazing tools, and I have personally used Hangfire myself with great success. But, they both suffer from a lack of flexibility and/or complexity in usage.
Quartz.NET suffers from an overly complex API, based upon configuration files, in a difficult to understand format, giving you no syntax highlighting or AutoComplete when you declare your tasks. In addition, the amount of code required to actually create a simple task sometimes feels staggeringly large and unnecessarily complex. The fact that it was "ported" from Java shows as you try to learn its API.