Windows 10: sihost.ext - Unknown Hard Error warning, now Advanced Recovery mode won't load, computer...

This morning my machine was giving me an error about the audio not working, so I rebooted. While restarting it checked for hard disk errors, which I hadn't seen it do before, but this appeared to go fine. When it finished restarting, on the login screen I got a "sihost.exe - System Warning" error window with the message "Unknown Hard Error." I am able to log into the machine, but then everything is black and every so often another window pops up saying "sihost.exe - Application Error: The instructions at 0x[long hex number] referenced memory at 0x[another long hex number]. The memory could not be written. Click on OK to terminate this program."


I was initially able to reboot and get into the Advanced Recovery screen, and tried following some of the advice that I found on this site for similar errors. I tried to revert the latest Windows update, but that failed. I tried to revert to a recovery state from two days ago, but that failed too.


After several more reboots I found that I was no longer able to access the Advanced Recovery functionality. When I try to start it with, from the login screen, shift+click on the power button and then on restart, it just brings up a blank blue screen.


When I try to get into BIOS or recovery mode while booting I'm on a Lenovo machine, normally F2 or Enter, respectively, works, nothing happens; it just keeps booting until it gets to the login screen and shows me the same sihost.exe error message.


I also can't load the command prompt, which is the other thing that was referenced by a lot of the similar forum threads that I'd found.


At this point I'm stuck and don't know how to proceed; I can't get to any of the Windows recovery tools or any other functionality so the machine is functionally bricked. At this point I'd be fine with doing a factory reset but I can't even get to the screen to do that. Any help would be much appreciated. Thank you.

:)

 

sihost unknown hard error

running Win 10 on a Toshiba. Third party Antivirus which has been running for two years without error. very few "Apps" Office 2013 running. not running outlook..

computer booths and login screen shows. login normal mode, background pops up for a few seconds then the screen goes dark. mouse pointer is on screen and can reach the Task Manager but nothing else.

similar in safe mode except that the screen fully loads then a sihost unknown hard error pops up. when i click "OK" the

screen goes blank.

I have tried to do a system restor and ipt atopped early in the cycle.

Any ideas or directions?

***Post moved by the moderator to the appropriate forum category.***

 

windows 10 sihost unknown error

Is there a fix for the April windows 10 sihost "unknown error"?

Thanks

 

Sihost.exe unknown error

Some sites which may help:

https://www.bleepingcomputer.com/forums/t/67793...

https://borncity.com/win/2018/08/23/windows-10-...

https://www.computergk.com/how-to-fix-sihost-ex...

Note: This is a non-Microsoft website. The page appears to be providing accurate, safe information. Watch out for ads on the site that may advertise products frequently classified as a PUP (Potentially Unwanted Products). Thoroughly research any product advertised
on the site before you decide to download and install it.

Please do not download any program which may be on these sites offering to fix this problem.