I'm assuming you posted this question with another account...
When you login use you apple id (the email you setup your account with) and the password you created for apple.
If you can't login to your apple id because you don't know the apple id or password you can have apple send an email to reset here https://iforgot.apple.com/iForgot/iForgot.html
The reason you would get an error like "An account utilizing this email address already exists" is because you are trying to create a new apple id from an email that already has one. You just need to recover the first apple id and then go from there.
I hope this helps, reply if you need further help
Hi thank you but you missed the point.
I'm not trying to create anything. When I search in the web for discussion topics and I click in the link, Safari automatically redirects me to a page to log in with my apple id. I do so and then in the first page that appears I have the options and results that I specified.
I had the exact same problem and here is how a could finally get through.
My "appleid" is just a regular word, it is not an email address or anything like that.
I once remebered that Apple asked me to log in with my email address rather then my "appleid" (using the same password).
I logged in in the discussion forum using my email rather than my appleid et voilà, I'm in, with my former "Apple Support Communities username" and everything looks fine as before.
So of course, the first thing I do is write about this issue and the solution I found.
I hope it will help others to work around this problem.
(Yes. Whether you like it or not this is a problem and not a normal behavior. Just google appleid and "Apple Support Communities username" and you'll find other people experiencing the exact same behavior. And NO, I was not "creating a new account" mistakenly, I was signing in.)