Whenever I tried to play a YouTube video in the most recent version of Firefox lately, it would only display the advertisement before the video for a couple of seconds before a dreaded "an error occurred, please try again later" message prevented me from watching that video or any other video for that matter on the site.
The error message was thrown on YouTube but also on third-party sites with embedded YouTube videos.
A quick analysis of the issue revealed that the error message was only displayed in Firefox, and there only if Adobe Flash Player was used to stream the videos to the browser.
The HTML5 player worked without any issues. How to find that out? You can right-click on the video to get information which technology is being used to play it.
If you see "About Adobe Flash Player" in the context menu, Flash is being used while "About the HTML5 player" indicates that HTML5 video is used instead.
What I did notice as well is that no video resolutions were displayed as available when I used the Flash Player as all were grayed out. If you monitor this closely, you will notice that the player tries each one of them and marks it as gray (unavailable).
So, switching to the HTML5 player on YouTube resolves the issue. The problem here is that it does not support all videos on the site yet. While you can play many in HTML5 format, some revert to Flash Player if installed on the system.
Here is a workaround for that
- First thing we are going to do is enable the HTML5 player on YouTube. Visit https://www.youtube.com/html5 and click on the request the HTML5 player button.
- This basically configures YouTube to use the HTML5 player whenever possible.
- The second step is to disable Adobe Flash so that YouTube cannot use it instead. This ensures that HTML5 is used whenever possible. If you don't disable Flash, it may sometimes be used instead.
- Open about:addons by loading it in Firefox's address bar. Switch to plugins and change Shockwave Flash to Never Activate from the menu on the right of its entry.
- You need to block the plugin as you will get the "activate Adobe Flash" prompt instead if you set it to ask to activate.
Other things you can try
While switching to HTML5 and disabling Flash worked for me, there are other things that you can try to fix the issue.
- Reload the video at a later point in time or immediately. This never worked for me but if it is just a streaming issue, it may work for you.
- Update the Adobe Flash Player. This is an obvious choice. Did not work for me as I had the latest version installed already.
- Upgrade your browser. Did not work for me either as I'm always running the latest version.
- Delete cache and cookies. Did not work either.
- Change the video quality. As I mentioned earlier, all video resolutions turned out to be unavailable in my case.