Yes there most certianly are and as you are not able to get E-Mail consistantly from the router either by direct connection of WiFi I would tend to think that it isn't setup correctly.
Use the Manula that came with the Router most likely as a PDF file on the CD and just diretly connect 1 computer to it open your Web Browser and type in the HTTP address and then enter your user name & password and get stuck into the settings. But before you do this it would be a good idea to make sure that you have the latest version for the router and install if necessary.
Routers need to constantly have the newest Software installed to keep them secure. You should also change your password from the default as well and use a Alpha Numeric String as a password as they are harder to crack You don't want to make it easy for the intruders do you. ;)
You'll also need to see if the Router is acting as a DHCP address sender and setup according to your needs. As there is a WiFi link here it's very important that you secure it as well as possible as these things have a range of up to 500 Mts and anyone within that range has the ability to log on and steal your Connection and download things that you will be legally libal for.
There should be an entire section in the manual devoted to securing the WiFi connection so it's important that you read it and follow the advice given there. If you much things up and can not get back in to fix them you can always use the Reset Switch which will return the uniot to the Factory Defaults so you can start again without a problem.
AS you didn't state a model it will vary the way that you setup the thing between models but page 8 here should be a guide for you.
http://tinyurl.com/j28xt
Col
