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Windows 11 users are reporting some installation failures when trying to update the OS, with an uninformative error not throwing much light on the cause of the apparent problem – although it’s an issue that Microsoft is ‘closely monitoring’.
Windows Latest reports that an error code 0xc1900101 is being produced for some folks when trying to update, and the operating system then rolls back to the previous build with no further details on the cause of the issue being provided.
This is apparently happening mostly with preview builds of Windows 11, and other error codes have been witnessed as well, Windows Latest notes, but the aforementioned one is the most commonly seen and reported on Microsoft’s Feedback Hub.
One user posted to the Hub: “All my physical machines updated ok, but on a virtual machine running either Hyper-V, VMWare, or VirtualBox, it almost gets to the end of the update, and then rolls back. Worse, on VMWare and VirtualBox, the virtual machine software crashes at the end of the update.”
Another observed: “Mine has the same problem. The first time I update the pc to the latest build it showed an error about my graphics driver so it rolled back. I was suspecting that the windows update corrupted my graphic driver as after rolling back my graphics card was not working, it just works after I reinstall driver. I reinstall the update later and it was a success.”
Microsoft has confirmed that it knows about the error which it describes as a ‘generic’ failure and an area that the company is watching closely.
Microsoft advised one affected user: “Thanks for taking the time to report this – error code 0xc1900101 is a generic error displayed when an update fails and rolls back for some reason. This is an area we monitor closely and can have different root causes depending on which build you were attempting to upgrade to and your setup.”
No firm advice was given, then, as to how someone might get around this gremlin in the works, but Microsoft does say that users should try updating to the very latest preview build (if they were attempting to upgrade to a previous version, of course).
Analysis: Some possible workarounds, but the waiting game might be best
There are various theories about the cause of this – and similar – update failure errors, including suggestions of app compatibility or driver issues (as we saw above), or even low disk space. But as Microsoft mentions, this is a ‘generic’ error and one which could have a number of different causes.
If you encounter this problem, aside from making sure you are attempting to install the very latest build, there are a few things you can try. It certainly won’t hurt to ensure that you aren’t running low on drive space, and maybe run a disk clean (it’s a good idea to do this periodically anyway). Also, we’ve seen another user report that disabling their antivirus resolved the installation failure of a recent preview build, and there are some further suggestions of potential action to take in this thread from the Microsoft Tech Community.
What’s also worth noting here is that this error has been a problem in the past, for example with Windows 11 preview build 22504 (back in November 2021). At the time, Microsoft’s advice was that users “may want to pause updates until we release a fix”, although in the past Microsoft has also said that those encountering this error code with Windows 10 should try to install the update again after a clean boot (find instructions here – and interestingly as observed above, another potential mitigation mentioned is to disable your antivirus temporarily).
In short, while you may get some joy from the potential solutions floated in the links above, your best bet might be to simply wait for the issue to resolve itself, providing you don’t have an urgent need to get the update in question up and running.