The only error :) maybe is not searching this forum for this problem. Maybe the following will help
http://forums.b2evolution.net/6-9-7-twitter-plugin-does-not-works

Hi
Thanks for your answer. I had read the post you mentioned before I wrote about the problem, but the case is no exactly the same. ednong says "The connection works, the log in to my twitter account was successful." In my case I don't even see the link "Click here to link to your twitter account" in Collections->Settings->Plugins...

OK Just installed and have the same problem as you show
Reading http://forums.b2evolution.net/is-twitter-plugin-down-or-buggy