Windows 11 Modem Driver Removal due to unpatched vulnerabilities
Microsoft is investigating Windows 11 update KB5074109 boot and modem issues. A recent Windows 11 security update has left some users confused and frustrated after their modems suddenly stopped working. While many initially assumed it was another Patch Tuesday mishap, Microsoft says the behavior is intentional and not a bug. The update removes legacy modem drivers due to unpatched security vulnerabilities.
Update removes legacy modem drivers due to unpatched security vulnerabilities
Following the January 2026 Windows 11 security update (KB5074109), reports began appearing from users whose dial-up and legacy modem hardware no longer functioned. Given the update’s association with other serious issues — including GPU glitches, app crashes, and boot problems — the modem failures were quickly lumped into the growing list of update complaints.
However, Microsoft later clarified that this particular issue was expected.
In the official release notes, the company confirmed that the update removed several outdated modem drivers from Windows 11. Devices that rely on those drivers can no longer operate after the update is installed.
Which Drivers Were Removed?
The update eliminates multiple legacy modem drivers that date back many years, including both 32-bit and 64-bit versions. These drivers were still present in Windows primarily for backward compatibility, but Microsoft says they contain unpatched security vulnerabilities.
From a security standpoint, removing them reduces the system’s attack surface — but it also means affected hardware is effectively deprecated overnight.
Windows 11 update breaks modems
While the driver removal was documented, many users never noticed the change until their hardware stopped working. Some even reported that newly purchased modems labeled as “Windows 11 compatible” failed immediately after the update.
This has caused particular disruption in niche but still-active environments, such as:
- Legacy phone answering and logging systems
- Industrial or specialized setups that depend on modem drivers
- Businesses still using older hardware for logging or connectivity
In many cases, manufacturers no longer provide updated drivers — leaving users with limited options.
Windows 11 modem driver removal: Can You Fix It?
There is a temporary modem driver removal workaround in Windows 11, but it comes with risks:
- Uninstall update KB5074109 to restore modem functionality.
- Pause Windows Update to prevent the patch from reinstalling.
- Use the time to migrate to supported hardware or a newer connection method.
This isn’t a long-term solution. Running an unpatched system increases security risk, especially if the device is connected to the internet or used inside an organization.
Microsoft is investigating Windows 11 update KB5074109 boot and modem issues
Microsoft’s move highlights a broader reality: security improvements increasingly require dropping legacy components. Most users won’t notice this change at all, but those who rely on older modems are discovering that Windows 11 can remove compatibility overnight, even if the device still worked before Patch Tuesday.
If your setup depends on one of those legacy drivers, uninstalling the update may buy you time, but the real fix will likely require replacing the hardware.
I have a 6 month modem on a new computer that was killed by this update. Microsoft published in 2023 that they were going to remove these files, and modem companies did nothing. StarTech and US Robotic modems no longer work on Winows 11.
You say “The update eliminates multiple legacy modem drivers that date back many years”.
I would like to have some idea of how ‘old’ my router–modem is:
1. How ‘many years’ old is ‘legacy’ in this situation?
2. Do you have examples of such modems?
Sure, it’s only a few seriously old modems that M$ has disabled. However, that’s not the point. What M$ is doing is pushing a precedent so that they can slowly begin disabling *not* so old and critical hardware. This is planned obsolescence at its worst.
I have been proponent of disabling all Windows 11 updates on home PCs for two years. I have been mocked relentlessly. Who is the sucker now :)
I would imagine that the bandwidth available to modems, is woefully inadequate to transmit all the telemetry, that co-pilot needs to upload, in order to train itself in future iterations.
Its like sweeping up the stragglers, and in doing so, removes any remnants of legacy data transfer, in order to “encourage” the update to a broad band connection, Microsoft’s way of “lending a hand” to the associated hardware and service industries.
I remember a similar story involving a poor old lady, who was running a laptop on a modem connection to the internet, using a version of Windows which could be upgraded. She received an update notification for Windows 10, she agreed to it, and the download took as long as a month, at the end of which she could no longer use her modem.
I hope the poor lady was not too badly traumatised by the loss of her family pictures, all the memories associated with them, and her inability to recover them, from the cloud storage she was using.
But then again consideration, sympathy, and empathy, are frowned upon in major corporations, because those human qualities simply don’t make money ..do they?
Peter Newton [London UK Linux user since 2004]