T-Mobile appears to have upgraded their built-in web filtering system, and it’s causing some users to have their web browsing blocked.
According to a tip from a trusted source, T-Mobile has “upgraded” their web filtering systems recently.
The source claims the new system supports HTTPS, whereas the previous system did not. It turns out many customers have T-Mobile’s web filtering system, called Web Guard, enabled and had no idea. The new system is just causing those customers to notice.
Web Guard is a feature available to T-Mobile customers on a per-line basis. It blocks certain content based on which one of three levels the filtering is set to. The content ranges from adult websites to email access.
Customers have been posting to Reddit over the last week complaining of random web blocking. Attempts to load things like YouTube, social media, and other sites are being blocked by OpenDNS. It seems T-Mobile is using OpenDNS filtering on their Web Guard service.
According to another source, T-Mobile has updated their internal Web Guard information page to lay out how the levels of filtering work. A copy of that text is shared below, along with a table of blocked categories for each level of filtering.
Safe Search: High and Medium filter levels enable SafeSearch, an automated filter of pornography and other offensive content that’s built into search engines (Google, YouTube, Bing, and DuckDuckGo).
When a user attempts to access a site that is “blocked,” a popup message appears: This site is blocked due to content filtering: [name of website]. Content filtering has been enabled on this line and is restricting access to this content. An authorized person on your account may be able to disable this restriction through the account management website. This site was blocked due to the following categories [lists categories].
Customers may also see ‘secure connection failed’ if the website is being blocked by Web Guard.
It’s unlikely that T-Mobile is actively enabling the Web Guard feature randomly. The assumption here is that customers had the Web Guard feature enabled from the beginning, but due to the upgrade it’s simply noticeable now.
It’s worth noting that this is a separate and unrelated issue to the recent Apple iCloud Private Relay issues the carrier has had.
Affected users should contact T-Mobile via any support channel and ask that Web Guard be disabled. It can also be turned off in the app or on My T-Mobile. If you have FamilyMode enabled, that overrides Web Guard, so you’ll need to change the settings in the FamilyMode section instead.