I just started getting this issue too... log in to game.. try and start... says cannot connect to server check firewall.

Edit: reset router and it fixed it

Nope, I pay for my own. Heres the run down of what I did:

-Went to my wireless setting: - Properties
- Internet Protocol Version 4 (TCP/IPv4) Properties
- Put Preferred DNS server: 8.8.8.8
- Alternate DNS server: 8.8.4.4
- Reset Router

Still having the same issue. =/

Still need help =/

Still looking for a solution.

hmm.... router firmware update? I scratching my head here. Only other thing I can think of is to post a system report so I could have a more in depth look at your PC.

I'm having the same problem, after choosing the champion i would want to play, it tells me : Unable to connect to the server. If you have a firewall, it may be blocking the connection. Please refer to your firewall's documentation. Would you like to retry the connection?
I've put it on the exception list/turned off firewall, yet it still say's the same.
I haven't been able to play for days now.

I won't lie. Pretty bad at this. 2 things.

A. I would I give you that information?
B. Would putting the info on this forum (to the public) cause any harm to me in the future?

Anyone?

Help!

Hmm. Same problem. I'm using the Mac client though..
I wonder what's causing this..