Safari 6 Won't Load Certain Web Pages

I have a new (August 2012) MacBook Pro. The initial YouTube page doesn't load in Safari. The page is simply blank. If I have a URL that takes me to a YouTube page, it displays fine and I can view the video, but I can't get the main YouTube page to load.

Have changed the MTU, but it didn't help. Have tried turning off Parental Controls, but it didn't help.

Any ideas?

Thanks in adance.

I have read all the posts in this thread and have tried everything suggested in these posts, feel sorry that none works. I have 2 parental controlled accounts on a core 2 duo iMac, both of them won't load Youtube and some other pages, quite clear it has to do with Safari 6 and Mountain Lion because the problem was not there with Lion or previous OS versions. I am just posting to add my Mac to the statistics. Hope Apple will come up with an answer soon.

can anyone confirm if they are having the same problem now on their ios device's after upgrading to iOS6, i cant log into the app store or ebay, but turn off wifi and use the phone network and it works fine.

I have the same problem with iOS 6, what we can do about it? 😐

I changed the MTU setting on my router to 1300 and this fixed the problem for me, and working perfect.

But this is not a great solution as if we were connect to a 3rd party's wifi network, that we can't change...

If you can, try changing the mtu on your router and this should get you going for now

May I ask why we are all sitting here on the apple support website, busting our balls to fix this hugely frustrating issue that so many people are having...and not being met with any response or help from mac support? At what point do they actually get up and do something about it?

We have all invested enough money in the product to be able to expect someone to fix the problem, instead of putting us all into a forum to sort it out ourselves. Having paid a lot of money for a mac I am now paying money to use a crappy internet cafe computer to load the pages instead??!