An outdated document and a customer complaint indicate that Comcast employees are (mistakenly) telling some customers of its Extreme 105 service that they cannot use their own modems and must instead rent equipment from Comcast.

"So I purchased the Zoom 5341J to take advantage of the 8 downstream channels now available here," a Comcast customer, apparently from Virginia who goes by the user name "ExoticFish," wrote on a DSLReports forum Monday. The customer continued:

Since then I had some issues, not speed related necessarily. So normal customer service was unable to resolve them so I E-mailed Comcast's "Executive Support' team." I got a call today from a guy. He was the rudest Comcast rep I had ever spoken to, EVER! Not only did he not resolve anything but he told me my modem is not approved for my package. I told him I previously had the SB 6120 on the same package for about a year now and both it and my new modem are on the approved modem list. He insisted that list is incorrect and I MUST RENT a modem from them to receive the correct speeds on Extreme 105! I requested he forward me this info and sure enough there was a document published (ID TLK1043) on February 26th stating "Only Comcast issued equipment ensures that the specifications are always met and not altered."

The document was posted on the forum and sent to the news site, Stop the Cap, which wrote about the incident yesterday. "Some customers are angry and frustrated to learn Comcast has stopped 'officially' allowing the use of customer-owned cable modems for its 105Mbps 'Extreme' service, insisting subscribers rent a company-supplied gateway for $8 a month," Stop the Cap's Phillip Dampier wrote.

A DSLReports story pointed out that a portion of the alleged Comcast memo contains spelling and grammar errors, possibly indicating that it isn't an official company document, but Comcast has chalked this up to a "miscommunication" between the DSLReports poster and a customer service representative. A Comcast spokesperson told Ars that he is "having someone try to figure out how to reach the poster, apologize, and fix this immediately... Xfinity Internet customers can either buy or rent modems."

"This is apparently an old document from when we first launched [Extreme] and when there weren't modems for sale at retail," the spokesperson wrote in an e-mail. "Four years later and there are plenty available on the approved devices list. The document is wrong and old, and we are working to figure out what happened."

“Only certified Comcast equipment”

The old document contains instructions to customer service representatives regarding the Extreme 105 service, which provides 105Mbps download and 20Mbps upload bandwidth. Along with a $249 installation fee, an FAQ in the document explains Comcast's policy on user-owned equipment:

Why do I need to use Comcast issued equipment? Only certified Comcast equipment delivers the ensured service speed attached to the customer’s account. Comcast allows customers to use their own equipment for all your other Internet packages, why not Extreme 105? Generally customers can use their own equipment and configure it as they see fit. But for Extreme 105, the configuration must be done and maintained at certain specifications. Only Comcast issued equipment ensures that the specifications are always met and are not altered intentionally or unintentionally. But I have a DOCSIS 3.0 Modem and N Router, why do I need your versions? Comcast installs equipment which have gone through extensive network certification process of Comcast and which have been proven in both laboratory and live network tests. This ensures that the equipment performs consistently and delivers the subscribed speed and services. Does the $249 installation fee include installation of a wireless router? Yes, the installation fee includes the installation of Comcast owned wireless router. Why is there a premium installation fee for Extreme 105? Extreme 105 is a premier Internet product by Comcast and the premium installation fee guarantees a speed of 105Mbps. A Comcast Certified Installation Technician performs additional tests which are not performed during installation of other premier internet service. Is the premium installation fee refundable if I disconnect the service in 30, 60, 90 days? The installation fee is non-refundable.

Recent use of the old document made it appear that a new policy was in place.

"The Virginia customer never realized Comcast changed its policies until he had service problems," Dampier wrote. "It was then that a senior representative insisted the customer switch to Comcast’s rented gateway device if he wanted his service fixed. Other customers still using customer-owned equipment and subscribed to 105Mbps service may continue to fly under the radar for some time, and there does not seem to be any national effort to contact customers about their equipment."

A policy to prevent customers from using their own equipment would be at odds with Comcast's aforementioned public list of supported devices, which shows a few dozen Arris, Cisco, Motorola, Netgear, and other modems as being supported on the Extreme 105 service. The list of supported devices includes the Zoom 5341J owned by the customer who posted on DSLReports.

Such a policy might violate Section 629 of the Communications Act, which says consumers should be able to use third-party equipment, "or would if we enforced Sec. 629," tweeted Harold Feld, senior VP of consumer advocacy group Public Knowledge.

Houston-based Ars editor Lee Hutchinson says he is required to use a Comcast-issued modem and router for his 50Mbps business class broadband, which costs $110 a month plus $5 for a static IP address and an "equipment fee" of $10 a month. That's presumably because Comcast wants to sell a service including remote management, port forwarding, DNS, and DHCP, even though Hutchinson doesn't purchase that service.

The complaint on DSLReports kicked off a thread of customers complaining about Comcast's modem policies. One commenter said that "Even if you own your own modem, Comcast may charge you a rental fee (by accident of course)," to which another responded: "At this point I wouldn't say that would be an accident. It has happened to people for many many years and many many times. Comcast knows of this and still does nothing to correct it from happening in the first place."

Perhaps not coincidentally, Comcast was ranked by Consumer Reports as one of the least liked Internet providers, just barely ahead of Time Warner Cable, which is set to be acquired by Comcast for $45.2 billion.