Hello,
I've been having this problem with my 3DS. Everytime I try to run a connection test, it fails, the 3DS connects with the access point. but gives me a cross when the access point connects to the internet . What's strange is that the browser works. i cant connect to eshop....
therefore I can't update my system..... and using the eshop....
I followed the steps Nintendo had to offer on their help site and even that didn't work.
i have tried solutions in many websites but the result is none...
by the way, i am using router TP LINK WR841N
please somebody help me 
thank you!