"I keep having to reboot my router to get back online."

If you are unable to get online, and rebooting only the router gets you back online, then the problem is most likely too much traffic trying to go out of your connection, either by malicious software (a virus, worm or spyware), legitimate software doing what it's supposed to do (some peer-to-peer filesharing networks) or legitimate software that is flaking out.

In every case where a customer has experienced this problem--rebooting the router gets them back online for some period of time, be it minutes or hours--the issue has been one or more devices on their network sending out a large amount of traffic. Here are some examples:

• A sorority had to reboot their Cisco router several times per day. A technician went out to troubleshoot the issue and after checking the router logs he saw two different computers on the network that continuously sent a large amount of data to a particular IP address on the internet. A lookup of who owned the IP address indicated it was owned by the company that makes the program Weatherbug. The technician located the two computers and both of them did in fact have Weatherbug installed. He uninstalled the program from the two computers and the customer never had a problem again.
• A business customer in Lansing kept having to reboot their router, and also noticed slow performance when it was working. After several visits by their equipment vendor our technician looked into it and determined their database server was infected with the Slammer worm that infects Microsoft SQL servers. The server was patched against the worm and rebooted, and the router was rebooted as well. The problem did not return.
• A residential customer purchased a Linksys router at Best Buy and after several months began having problems. He replaced the router thinking it to be defective but the problem persisted. After speaking with our support department it was determined that he was using a peer-to-peer filesharing application known as Bittorrent, which continuously uploads portions of the file the user has downloaded. This continuous outbound traffic was bogging down his router. He went a week without using Bittorrent and had no problems.
• A T1 business customer could only get online for a few minutes after rebooting their router. They had no problems seeing their router on the network, and we could see their router fine on the T1, however they could get no traffic through the router after it being online for a few minutes. We instructed their engineer to get into the router and look at the traffic that was trying to go through it (as our technician did in the first example) and all the traffic was originating from their server and going to the same IP address on the internet. A lookup of the IP indicated it was the Symantec Liveupdate server. Apparently the Symantec Corporate Antivirus product installed on the server was malfunctioning and was trying to connect to Liveupdate hundreds of times every second, overloading the router with requests. The engineer uninstalled/reinstalled the product and had no further difficulties.

Customers having these problems are advised to first try to eliminate the number of devices connecting to the router. If multiple computers are connected, it could be only one of them causing the problem (see "I can get online, but slowly" for more information about performing these tests). Also eliminate non-computer devices from the equation, as we have had customers with network print server devices that also begin sending out large amounts of data.

If nothing can be determined by eliminating devices, plug a computer (with a firewall enabled) directly into the DSL modem and try that way. If the problem persists, contact technical support.