Airport express over ethernet blocks my wifi
Hi.
I have a wifi network via a modem from my ISP and I want to extend it with an Airport Express.
When I connect it over Ethernet, I can configure it to extend the network, but despite having a strong connection (i.e. 4 bars on my MBA, iPhone, etc.), I can't access the internet. There's just no access.
If anyone has any ideas about how I can fix this, I'd be extremely grateful!
Thanks
OS X Yosemite (10.10)