What ISP Service do you have? Cable or DSL?
What ISP Modem do you have? Stand Alone or built in router?
What ISP Modem make and model do you have?
Ensure DNS IP addresses are being filled in under Setup/Internet/Manual?
Turn off QoS options.
Turn off Advanced DNS Services if you have this option Setup/Internet/Manual.
Turn on DNS Relay under Setup/Networking.
Setup DHCP reserved IP addresses for all devices on the router.
Ensure devices are set to auto obtain an IP address.
Set Firewall settings to Endpoint Independent for TCP and UDP.
What wireless modes are you using?
Try single mode G or mixed G and N?
What security mode are you using? WEP, WPA? Preferred is WPA-Personal and Cipher type to AES only if your device support this.
I have a Cable service. As far as I can tell the modem is just a basic cable modem with no router it's a Scientific Atlanta model: EPC2203.
I did all of the above(except there was no option for advanced DNS). Was I supposed to fill in a specific IP for the primary/secondary DNS servers I just entered in IP similar to the router IP just not the same IP.
The wireless mode was mixed G and N and security was WPA-Personal. After doing all of the above I lost connection to the internet completely. All laptops/computers could connect to the router without any problems but the internet connection stopped working completely I had to connect the modem directly to this PC to get any internet. I'm really not sure what went wrong.