Une erreur est survenue, veuillez réessayer plus tard.

I also have this issue, but not on all videos, and when it occurs, a hundred refreshes don’t change anything.
This problem appeared for me, so to speak, overnight not long ago...
As a precaution, I updated Flash & Firefox, disabled most of my plugins/add-ons, but without success.

Could it be a codec issue with certain videos?
What technologies does YouTube use apart from Flash? (or could an update solve the problem)

In any case, I'm managing it while waiting for a more viable solution with DownloadHelper ( https://addons.mozilla.org/fr/firefox/addon/video-downloadhelper/ ), I download the problematic video and then play it directly from my desktop.
I hope this can help some while waiting for a better solution :)

http://en.kioskea.net/forum/affich-113416-an-error-occured-please-try-again-later

you need to delete all the cookies!!!

Tool --> Clear my traces --> Check all and there you go!!
(Personally: it worked for me)

Hello, I did what another user said, I quote:
Regarding the current problem, here is a solution you can try:
Launch your reaplayer program, go to the general menu and select "preferences..." then go to the sub-menu "download and recording". Then disable the "enable downloading and recording from the web..." function. Then click OK, restart Mozilla, it will work again (regarding the impossible viewing for the past few days via YouTube/Mozilla Firefox).
And it works!

Hello,
I found the solution, download the software from this link: http://www.auslogics.com/en/software/registry-cleaner/download/
Then install it, and perform a scan and repair.

Another, somewhat simpler remedy is to change the format of the video for those that offer it, while waiting for something better.

Hello everyone!

I have exactly the same problem (An error occurred, please try again later), and this issue only occurs on certain YouTube videos (other sites like Dailymotion work very well). Sometimes you have to refresh the page several times before it finally works, and sometimes refreshing makes no difference.

My browser is Google Chrome.

I am surprised that, on all the forums discussing this problem, absolutely no solution has been found! It’s as if this problem has NO solution...

If anyone knows one, it would be great for me and everyone else with this issue to let us know.

Thank you in advance! I’m crossing my fingers...

I found a trick, in the address bar you need to remove everything that has nothing to do with YouTube. See the example below.
link that doesn't work.
http://translate.google.com/translate?hl=en&rurl=translate.google.com&u=http://www.youtube.com/watch%3Fv%3DHw35mNc970Y
link that works
http://www.youtube.com/watch%3Fv%3DHw35mNc970Y&rurl

I removed from the beginning of the first link up to http:// and from =translate to the end and it works perfectly.

this is my case with forum links to videos on YouTube.

I sent it before specifying that this is exactly the video I wanted to see.

Basically, tidy up the address bar.

This error may come from the browser; on my end, I switched to Google Chrome and it worked, because I was on Firefox before.

I sometimes have the same problem with YouTube videos. Personally, I refresh my page and the video works, but if it happens to you every time, there must be an issue with your computer or your web browser, even though it's strange that this happens on YouTube but that Wat TV and Dailymotion still work...