If you are a Google+ users and also a Google Apps users, you must be tried to use your Google Apps account for your Google+. I did try to register on Google+ few months ago, when they just launch their new social product. At first, all gone well for me. My Google Apps account works for login to Google+. But i don't know why, after some days using it, it's not working anymore. I can't access my account. The message is that Google not yet available for Google+ services. But why? I thought i did registered, and used it, and all work fine.