I have the same problem. I didn't see a resolution on this thread. Over and over, over the last two weeks. Even when I went to Apple support communities and pasted in the full message I get, and selected another thread with that same message, I was redirected to this same message. "Looking for something in Apple Support Communities?
The page you tried was not found. You may have used an outdated link or may have typed the address (URL) incorrectly.
Please visit the main page of Apple Support Communities for links to discussion areas."
And when I select the main page, I get returned to this same message.
I recently upgraded from Maverick 10.9.5 to Yosemite 10.10.3 and I tried both Firefox and chrome. It also ruined my ability to use iphoto. Luckily I had bought Aperture so was able to upgrade that to work in lieu of iphotos, which I only had as the original Maverick upgrade. the new Photos does not work for me. I need access to the metadata. I feel that Apple is just messing with us long-time Mac users and was trying to figure that out when I was effectively banned from replying or asking a question on most threads and completely blocked from the ones that discuss this issue.
I'm using Safari 5.1.0, the URL is "https://discussions.apple.com/". In the following window I log in and taken to a window that has the following message: "The page you tried was not found. You may have used an outdated link or may have typed the address (URL) incorrectly."
"Please visit the main page of Apple Support Communities for links to discussion areas". I selected the highlighted "Apple Support Communities". The same window opened with this URL message: "https://discussions.apple.com/backsoon/error.html".
No, I do not have another browser.