Windows 10 endless reboot after failed update

I'm trying to fix two Win 10 computers that recently downloaded an update and now they are stuck in an endless reboot. They attempt to uninstall the update, fail, and reboot, continuously. By booting to a Dell recovery USB I can get to the advanced startup options. It gives me the option of rolling back the update, but this fails. It does not give me the option to boot into Safe Mode; I tried to do it by command prompt, but it didn't recognize the command. One of the machines has an automatic restore point, but the restore failed. I tried the "net stop wuauserv" command, but it says this service name is invalid. I really don't want to just reset or reload the computers, but I don't know what else to do. Any ideas?
PTG SupportAsked:
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Raj ShivaramSenior ArchitectCommented:
Have you tried to boot into Windows 10 with your Windows Installation Media and select Repair your computer to enter Troubleshoot > Advanced Startup Options > Command Prompt. You can use CMD to run commands.
You can try the following commands and hit enter after each line of command:

Bootrec /fixmbr
Bootrec /fixboot
Bootrec /scanos
Bootrec /rebuildbcd
You could try to delete pending.xml
del C:\Windows\WinSxS\pending.xml
(make sure that your bootdisk sees the unbootable system as c:)
PTG SupportAuthor Commented:
Thanks everyone for the advice; I'll definitely use it next time. I was pressed for time and was able to get the product keys for Office, so I decided to reload both computers.

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Seth SimmonsSr. Systems AdministratorCommented:
No comment has been added to this question in more than 21 days, so it is now classified as abandoned.

I have recommended this question be closed as follows:

Accept: PTG Support (https:#a42455745)

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