Deleted windows.old now PC wont boot.

Dunlop0078

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I deleted my windows.old file from windows 10 to free up some space. After that I shut the computer down and went to bed the next morning it wont boot, I get past POST I think but never make it too the windows logo, i then get this message "the boot configuration data for your pc is missing please use startup repair".

I downloaded the windows 10 media to a usb stick and am attempting a startup repair now but it has been stuck at attempting repairs for a while now.

This is happening on a dell latitude 3540 laptop.

 
Solution
I would think a hybrid drive would be more likely to have the problem than a standard SSD.
many of the windows core files would be used often and the caching system on a hdd /ssd hybrid system will have the core windows files in the solid state cache. When you then installed a new OS, the new files will not have been fully migrated to the solid state cache. When you delete the windows.old then the solid state cache would be expected to clean up the files and would take the time hit after you deleted the directory.

the files in windows.old would not have been timed out of the solid state cache after a few days, they were in use for months. Deleting the files triggers the removal from the SS portion of the system.



Well startup repair literally took like 3 hours, after the two hour mark I figured it wasn't going to work so I posted on here looking for a solution. But an hour later startup repair completed and now it works just fine. I have no idea what caused it in the first place.
 
Only reason I can think of that removing windows.old would cause a system to not boot would be a firmware problem in a solid state drive. The firmware can get behind on the TRIM commands and the drive does not respond in a timely manner until it finished the firmware TRIM / garbage collection commands.

Just a guess, fix would be to boot into BIOS for a few hours to give the SSD firmware time to finish. Note: you might want to run crystaldiskinfo.exe and check your SSD firmware version with the versions that are current for your SSD.
 


Hmm, I dont have an SSD in my laptop its an SSHD hybrid drive, do you think what you described could occur on an SSHD as well?

I also created a new volume using space from my C drive the same night I deleted my windows.old file i dont know if creating the new volume could have somehow caused it and this windows 10 install was only like three days old when this happened if that helps.
 
I would think a hybrid drive would be more likely to have the problem than a standard SSD.
many of the windows core files would be used often and the caching system on a hdd /ssd hybrid system will have the core windows files in the solid state cache. When you then installed a new OS, the new files will not have been fully migrated to the solid state cache. When you delete the windows.old then the solid state cache would be expected to clean up the files and would take the time hit after you deleted the directory.

the files in windows.old would not have been timed out of the solid state cache after a few days, they were in use for months. Deleting the files triggers the removal from the SS portion of the system.



 
Solution


Well that makes sense to me. Thanks for the explanation.
 
I ran into a similar problem after attempting to take ownership of windows.old and delete as much of the files as I could in safe mode. I wasn't able to fully remove everything because explorer claimed a process had some of the files opened. However Process Explorer showed no open file handles in windows.old. Very perplexing. When I rebooted, I got past the post screen but was stuck at a black screen thereafter with no mouse cursor or loading icon.

Per your suggestion johnbl, I tried leaving the machine at the BIOS screen for several hours and it didn't help. I was unable to use the Windows 10 startup recovery feature successfully, but rolling back to a saved restore point corrected the problem, thankfully. I discovered that my SSD firmware was behind and updated to the latest firmware. I'm still stuck with the windows.old directory and I'd really like to reclaim the 500mb on my tiny SSD.
 

Okay so I did the exact same thing last night. It came up in action centre something about removing an old version of windows to free up space on my ssd and when I clicked on it, it vanished from the action centre. After about an hour of trying to figure out how to get ownership and remove permission from the folder etc, i finally deleted it. Went to bed quite happy with myself. Woke up today to find my computer wouldn't launch, it comes up the MSI motherboard thing like it does all the time then to the windows logo with the spinning dots and then goes to a neverending black screen with the same dots. Looked around on some forums etc. Put the windows stuff needed to reinstall through a usb on my usb and tried launching through it but it either takes me to the same black screen with the dots or a kinda beige looking coloured screen. Absolutely no idea how to fix it, i've tried whatever microsoft support say but they're fairly useless. I've been on what they called the "hard reboot" screen where you can reinstall windows but it says it cant do it even when i say it can wipe all my files. No restore point either as i wiped my computer a few weeks back.

Nevermind, tried with a different USB and it went fine.