Forum Discussion
Gordony
Feb 03, 2026Iron Contributor
What should one do if the Windows 11 update fails to install?
Windows 11updates (including upgrading to 25H2) fail with an error after downloading and installing less than one-third of the way, and success is never achieved. How can this be resolved?
KapilArya
Feb 05, 2026MVP
Hello,
You can try manual upgrade using Windows 11 25H2 ISO file.
Follow these steps:
Download Windows 11 25H2 ISO from the official Microsoft website.
Double click on it to mount it to a DVD drive.
Then go to DVD drive, double click on setup.exe to proceed.
Follow on-screen instructions to complete upgrade.
For detailed instructions, refer this step-by-step guide:
Let us know if this helps!
Note: Included link in this reply refers to blog post by a trusted Microsoft MVP.