Updating the firmware. But Linksys didn't grasp the market its going into. Most will not want to do this step and will exchange the unit instead.
Bob
Some of them get connected for 5 minutes, and the other luckily enough get around 2 hours.
Everyone said that they need to turn off eveything (Broadband modem, router and PC) then turn on in order (Broadband modem, router then PC)
Other solution is to clone the mac address and set MTU 1400.
Other simply said change brand..
Other information, Linksys warranty for free exchange is one year, so how old is your router?
That's what I collected from google...

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