RS-Prerelease build 25309 out to Dev Channel

Well will wonders never cease. Unplugging that external HD and restarting the update WORKED. Glory BE! I have no clue why that was the problem, but I have to say I'm sure relieved!

Connected external drives have been causing problems before on upgrades. Not really a surprise. 🤷‍♂️😎

Error installing after rebooting. I just restarted it without writing down the hex code, sorry. It took 6 min. to download, and the first reboot was after 28 min. I did check to make sure there was enough free space on the C: drive. If it fails again, I'll go delete the update files before retrying. This is the first time I've run into this in a long time.

Appreciate all the feedback in this thread. Will add some comments for folks who are hitting issues.

C1900101 is quite possibly my least favorite bucket of bug. It's driver-related and it quite frequently temporary. Install will fail once with that error and then immediately succeed on retry, with no changes in between. It's frustrating to say the least! As mentioned (by fg I believe), the "extended code" is important when seeing this error. If you hit it, please include the full error code, such as: 0xC1900101-0x2001

On to the FLTMGR.sys issue. This was something we saw internally before release, but it was a VERY small number of devices. Didn't have a reason to believe it would be widespread, but it's obvious folks are hitting it. We do have an active but on it and it's being investigated. There's a second bug in this space that we believe is driving a second issue as well. (One bug causing two separate issues/outcomes.) Actively digging in, that's for sure!

For the folks who hit the "file missing" errors, please do file feedback. There aren't any known publishing issues, so if it's true that a file is missing off the download server, we'll need to know which one so we can trace why it didn't land correctly.

Thanks as always for the feedback and for the details of what you're hitting. We're always working to improve and your feedback helps us get there!

Thanks CK. Looking in Update History shows code 0xc19000101. When I tried to download Setupdiag, I got Debugdiag instead which yielded a screen I couldn't figure out what to do with it. Back to more head scratching unfortunately.

Update: Searching found suggestions that this is likely a driver problem. Everythig on this Dell desktop is and has been working with no apparent problems, and I've had no problems running updates through 25300, so I'm still scratching my head.

After trying two times to install build 25309 and both times reverting back to Build 25300. I will wait until next week to see if they fix the problem. My other 2 computers were installed without any problems.