I can't play videos on the internet anymore.

Hello,

I made some changes to the settings (notably removing the add-ons that were bothering me) and I must have altered a setting unknowingly: I can no longer watch any videos online.
I am using Internet Explorer 9 and I have a Windows 7 PC.

I have done quite a bit of research online, especially on how things work to find the checkbox or the software to reinstall. And now I'm at a loss.

I have reinstalled (a large number of times) Adobe Flash Player.
I also updated Java (which was already at the right version).
I cleared the cookies.
I checked in Internet Options and "ASP scripts" is enabled.

On Google, the videos work (M6 replay among others).

But I prefer Internet Explorer a thousand times and I would like to get back the configuration that allows me to watch videos on this browser.
Does anyone know how to guide me?

Thank you
Have a nice day.