I've been asked to deploy, but I cant make the magic happen

I've added a couple of lines to a file, let's say it builds to be foo.dll. It's part of more then one dll file, but it's the core dll. What I did was that I added a couple of lines so it should add some log data to the database. It should not affect any other files what so ever.

So i tried to deploy it. We don't have the magical one click deploy, we are just copying the right files to the right place. So now, since i have a change in foo.dll, i thought for myself that i just could copy foo.dll and the server would be happy.

I was wrong. Browsing the website i now get "Generic Errors", dont know what that is. I've also tried to copy all the new dll files (4 i total) but that did not solve the problem either.

The error it gives are

Http Error 404.0 not found

Module: ISS Web Core Notification: MapRequestHandler Handler: Static File Error Code: 0x80070002

replacing the new foo.dll with the old one solves the problem. and i've tried to restart the webserver. :-(

I asume you have "published" and not just "compiled" your Web? You also need to take care off the "Solution Configurations": Debug and Release.

In a normal publish process you would change the configuration to release and publish your project into another folder.

After you have done that you just need to collect the desired files and upload them. Keep in mind that you need the newest version of you web project. Maybe there are some changes online that your local project hasn'T. This would cause such problems.

We don't have the magical one click deploy

Why not? It's not magic, and it's pretty easy to set up. Get any continuous integration software (I would recommend BuildMaster since I am a developer for it and it's free now) and you'll never have this problem again.