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When redirected to Cox log in for HBOGO and entering proper username and password I end up on a error page. The error page is Error 500 with a message like "The webpage encountered an error"
Regardless of the reason I am able to view any show by following the steps below.
1. First thing you do is sign in from the HBOGO home page using the sign-in link in the top right.
2. Go to the show or video that you want to watch
3. Add to watch list.
4. Return to HBOGO home page and open the episode from the watch list bar at the bottom.
5. Click Play and enjoy!
The COX or HBO website implementation of the log in redirect fails either on very long URL addresses from the HBO site or when trying parse additional data filters that are applied such as season filters
As far as i can tell Re-authentication is attempted periodically when viewing and submits the URL you launched the video from. This can cause time outs as well causing failed play back.
I can consistently repro this using The wire series season 1 episode 1 with a filter of season 1 applied and trying to log in or logging in from the home page and navigating to this episode and playing it.