XPS 8930, restarts hangs after Avast removal

You could also try this:

1. At desktop, open a CMD prompt window, Run as administrator
   
   
2. At the prompt, type in: chkdsk c: /r and press Enter.
   Accept offer to run chkdsk at next boot and reboot. chkdsk will run before Windows loads so be patient. You can review the chkdsk log for any "unfixed" errors.
   
   
3. Back at the desktop, open a CMD prompt window, as in #1
   
   
4. At the prompt, type in: DISM.exe /Online /Cleanup-image /Restorehealth and press Enter. Be sure to include a space in front of each / and note any error messages when that's done.
   
   
5. Assuming no unfixed errors in #4 , at the CMD prompt, type in: sfc /scannow and press Enter. Be sure to include a space in front of the / and note any errors when that's done. You can also look at the SFC detail file which gives you info on what files, if any, the most recently run sfc couldn't fix and will have to be manually repaired (eg, uninstall/reinstall the corresponding app).
   
   
6. Assuming no "unfixed" errors in #2, #4 or #5, reboot PC and test...

Thank  you, fireberd. So even though my scannow command showed OS problems fixed, you feel that the problem is with the OS and not Dell? I will familiarize myself with the process and making a bootable flash drive. Appreciate the response; will provide update when possible.

Thanks Ron for additional options. They do require reboot, which is the problem I'm having but I will try when I have time to beat up the PC--or be beaten by it! Will let you know. Appreciate your time. Susan

Good point Chino. Would I use the option under Dell Repair for a clean install or an ISO copy? It's an excellent option to have and I appreciate the suggestion.  Susan

If OP spent 2 plus months to repair this machine, I'd think that 2 plus hours of a clean install of Windows 10 (or 11) can bring this machine back to its powerful glory days.  Just straight up Windows, no Dell bloatware.  I just update OS on one with stock i9-9900k pairing with a GTX 1080 and it's still screaming fast in W11 22H2.

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@GloryB wrote:

1. Avast was horribly stubborn to leave and left my system in shambles (hung boots, reboots). This started a 2+-month odyssey of problem solving starting with the hung Power On boots [Dell screen with circling marbles] advancing to the current hung Restarts. 

2. Scannow found and repaired corrupt Windows files.  I tried using Dell Support Assistant for updates but I believe Win 10 hates it and the attempted downloads and app disappeared after I recovered my crashed PC. Right now I can power the system off and on but if I use Restart I'm back to the looping hang and need to use my USB Recovery thumb drive to get my system back. 

3. I started on the Commodore 64

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3. Yeah, I had one too, but I generally consider my Commodore Amiga-500 my first real computer (having a 40mb hard-disk and 3mb of memory made a big difference). I used it for 3 years, and then my wife used it for 3 years.

1. Sometimes ... these programs (like Anti-Virus) that dig-in real good have a "Uninstaller Program" that you can run on the system after doing the normal Windows uninstall.

2. This is troubling. That should not happen. Sounds like maybe your main drive has (coincidentally) decided to start going bad. Have you check it's SMART status?

If it checks good and/or acceptable, I suggest you first backup and then try @fireberd recommendation (as it is easier).

If that doesn't work ... well, you already have your backup so just clean-install Windows as @Chino de Oro suggests:

https://www.microsoft.com/en-us/software-download/windows10

or

https://www.microsoft.com/software-download/windows11

If your C-Drive is not a bootable SSD, I would get one and clean-install Windows to that instead of any spinning-platter HDD.

This was done earlier today (hence I'm on this forum as part of system testing) and I did the following:

• Backup data from all user folders, export all bookmarks from browsers.  Save to external drive.
• Go to Dell site and download latest BIOS, chipset and ME drivers.  Save to external drive.
• Create a Windows installation USB drive using MS Creation Tool.
• Restart PC and F2 to get in BIOS settings, use Data Wipe feature to clean the NVMe drive.
• Unplug ethernet and restart PC with Windows USB drive plugged in.  Windows should boot from USB drive and follow steps to install Windows.
• Create local account in the last step of installation as preference choice for user.
• When installation complete, customize all features to your liking.  Manually install chipset and ME drivers.  Plug in ethernet and set your network to private.  Run Windows update and optional updates to get all your drivers (instead of using Support Assist or Command Update).
• While Windows update running in the background, restore all data back to appropriate folders and import browsers bookmarks as well.
• Re-install applications and customize privacy settings in Windows and browsers.

System will be running extensively for a few days and all apps, games will be testing for both functional and performance.  Some examples, speed test and large downloads to measure network throughput.  Video ripping, encoding and rendering to benchmark graphics.  Editing and authoring a DVD to test (Adobe) application.  Any issue or unsatisfactory performance will be investigate for better resolution.  After everything runs well, the system will be changed to oc lv 1 performance mode (unlocked) and testing again for system stability, if performance gain is significant enough, if not, will revert back to locked mode.

Windows 11 is a bit harder to deal with comparing to Windows 10.  Because everyone knowledge is different, I am only able to describe how I did it.  If you are interested in working on your system and having question, just throw it here.  I can help with what I know.

Go to step 6 and create the bootable flash drive with the Media Creation tool.

Usually you will get the latest version, which I think is still 21H2.  22H2 is out but it was an optional advance copy on my Win 10 laptop.  You should be OK with either version.

FWIW, Win 10 22H2 was installed on my XPS 8930 via Windows Update this week and works fine. So I don't think there's any concern about creating a Media Creation Tool with this version for a either clean install or a repair...

Thanks EVERYONE for comments/input. I'm listening to all of you and starting to get a plan together  for saving my pc. Looking forward....

Everyone who responded helped me tremendously and I encourage anyone in a similar situation seriously consider all options given. RoHe (Ron) helped me assess my hardware but even after positive reports, the restart continued to hang. The bootable flash drive suggested by fireberd resulted in a successful restart of a Windows update (which was my major concern). All suggestions will help me in the future. Thanks. Susan

Glad I was able to help and happy it was successful.