From searching I can see this has been asked time and time again, but not adequately enough, so here goes. I'm a hobbyist developer with no budget. A program I've been developing has been in need of regular bugfixes, and me and users are getting tired of having to manually update.
Me, because my current solution of updating a text file through FTP and my download links on the website, and then hoping users will see the "there's an update message", and finally getting them to then be bothered to manually download the update, well quite frankly, is abysmal.
Users, because, well, "Are you ever going to implement auto-update?" "Will there ever be an auto-update feature?" And if I happen to screw up the update process, pitchforks start arriving.
Over the past I have looked into:
It's quite disappointing that the situation on Windows is like this when you've got really nice and simple implementations for Mac OS X like Sparkle.
Implement it yourself! It will be fun. Create a separate application that only contains update logic i.e., fetch the files online, download them, replace local files, and show that visually to the user.
So your main application could check for updates, and if they exist it would prompt the user with the possibility to update. If the user wants to, it will run the update program, close itself (so the update can happen) and presto.
The only things you need are readily avaliable in C#, FTP access and IO.
Edit: I know it's not something terribly easy, but it's a perfect chance to learn:
These are all things we all need to know well - If it takes some weeks to code an updater it means you were needing some weeks of learning. If you don't need to learn, time to hone your skills! If you don't know if you need, time to find out! :)
Note: I know I do need to learn better file and network I/O