Same here. Aura never is a problem, but I think visiting her is not really the same as other friends.
Others work sometimes.
I do have the *feeling* that it works much better if you use a high-bandwidth internet connection (e.g. LTE if you are in reach of a station).
It barely works on a 368kBit/s DSL line.
I'd assume there is a timeout in the App that just fails the visit before the necessary data is loaded.
It is not a bandwidth issue, although that could be one thing that causes the error function to kick in.
There are three friends I cannot visit under any circumstances. I have tried in different environments and on different devices. These three are just incompatible at all times.
Actually one of the three I could originally visit, but have not been able to do so for quite a while. The other two I have never been able to visit (but can exchange gifts with).
Every once in a while another kicks out, but that is much more inconsistent.
If you go back to the beginning of the Friends, an error caused a much more serious reaction - generally the game crashed totally and after a restart you lost all progress. I suspect the programmers then put in an error subroutine that automatically kicks back to the Home screen if certain conditions are not met after a certain period of time (which is nice in that it prevents progress from being lost). I don't know what those error conditions are, but it does result in some friends being "unvisitable" (for lack of a better word).
I have probably lost at least 1000 Kudos by this point but, since there really is nothing to spend them on (how many Sheep topiaries do you really need), it is not all that big a deal.
Still having an issue visiting Friends. There are three that I cannot visit at all without getting an error, and every once in a while others don't work at all.
Anyone else still having this issue?