1. Purchase The Orange Box.

1.5. Purchase the episodes by themselves before November 15th 2024. (if you didn't do it before 11/15/24 then you have to do step 1.)

2. Go to The Orange Box page, this is the only way to access the page for Half-Life 2's episodes.

3. Press "Play Now" and install.

4. When its installed, go to your downloads and press Launch.

It should work.

This also works for Lost Coast.

Lesson of the story? Just use the new Half-Life 2 feature of switching between episode 1, 2, and Lost Coast.