Won't Play videos on youtube

I have having the exact same problem. Videos play fine on my iMac, but when I try to open them up on my Macbook it's just a black window with no play controls. I haven't changed any settings and just boom, one day it stopped working. I tried updating to the newest version of flash but that didn't do it....Hopefully someone will have an idea as to what is wrong

Same problem here. Safari won't play YouTube videos but I can view on Firefox.
Updated Flashplayer two days ago. I can view the YouTube videos when they are embedded on Facebook but none on the website. Just a black screen.

same issue, tried uninstalling the current Flash Player and reinstalling 10.2 again. reset safari, emptied the cache, verified and repaired disk permissions and uninstalled and reinstalled Safari... whats going on!!!!???!??

quit safari
right click on safari
get info
open in 32bit mode
reopen
it will be fine afterwards

the new flash update is affecting the 64bit mode of a lot of macs/safari/youtube it seems.

this fixed mine and many others

come on Adobe, get it right

same problem here. what's going on??

I don't think this is the reason for the problem. I have a Macbook and an iMac both running Snow Leopard and YouTube works on the iMac just fine but it doesn't on my Macbook. So the problem isn't consistent.

Can I join in too? Same problem, except I have no other machine to test on, only my Mac and I would need the fix in 2 letter words only! Please type slowly.
Thanks all.

How do I close Safari and get info?

Macbook 4,1
Go over your safari in your dock and "two finger" click.. hit quit...
then go into options show in finder.. once your finder file opens up you can click on the safari icon to get the drop down menu. Then hit get info.. there will be an option to click the 32 bit mode.. close out and re-open safari.. i worked for me too.

Awesome I just posted a new link with this.....I believe since they changed HTML and stuff on the WWW, things are scetchy YIKES i hope they find out something soon

Thanks all, only took an hour to find 'get info' !! Maybe Apple can now employ me now I'm an expert?All the videos are working again, albeit with a deadly slow stutter because of my crappy 384 line. Any tips here on making more money to upgrade to a faster line?
The kind fellow that helped me change to HTML5, I see it does not show anymore ? Let sleeping things lie?
Oh yes, how do I set the volume in You Tube to be permanently[when I open it] at half way as I read at night when others sleep? During the day is fine, I see how to shift it.
Ta ta

This suddenly happened to me, too. Spent hours yesterday and this morning trying to fix this - tried verify disk, repair disk, uninstalled and reinstalled flash about 20 times...about to pull my hair out. Found this today and changed to 32 bit and everything is fine. THANK YOU for taking the time to help others!

Will we be able at some point to switch back to 64 bit? Will Adobe eventually fix the problem? What will be the negatives to running in 32 bit?

Thanks again!

Thanks joeapple1, after your advise everything back to normality.