Could not insert new outlet connection [duplicate]

Answer 1

Just got the same issue on Xcode 4.6.2.
Tried solutions presented in different answers/comments, but it still didn't work.

Then all I did was to just:

1. save all my work;
2. just quit Xcode & load it again;
3. then I was able to insert the new outlet connection successfully.

Hope this will save some time/frustration for somebody else.