When I was testing, I had this problem once but I was unable to reproduce it again. I would like to get an idea on what usually is the cause of issues like this:
1) User Blocked and could not activate after registration: I have set up Registration Type to "Require User Activation". After the user completed the user registration pages, it then took them to the last page where they need to type in the activation code that was sent via email. User did not receive that email. I then checked the backend and I saw the user's status as "Unpublished" and "Key activation pending" with an orange key symbol. In the email activity, there is no activation email on queue that was supposed to be sent for this user neither. When I tried Forgot my password from the front end for this user since the activation email was not sent, I saw the "User Blocked" message (screendump below). What is usually the reason for this behaviour? Again, I wasnt able to reproduce it since the next time I tried registering another account, I was able to create that without any issue. But this is bugging me on why the first attempt didnt work and had this odd behaviour. Why was the user blocked, why was there no activation email sent, etc.. Since you guys troubleshoot so many cases, I wonder if you had come across similar issue before..
2) Language Variable: In the screen dump you can see that the language variable is shown as "COM_EASYSOCIAL_USERS_USER_BLOCKED". Why is that? Do I need to update any language file?