Disk Cleanup and Windows 10 boot Blue Screen / Critical Service Failed – Disable drivers signature enforcement, Unsigned Drivers

Quick Post & surprising follow up to the workaround for Windows 10 Critical Service Failed Boot Blue Screen (Recovering from Windows 10 boot Blue Screen, Critical Service Failed, Disable drivers signature enforcement, Unsigned Drivers)

*update 2017-05-19, found this thread on reddit with a safer fix/workaround: seems installing the new Windows creators update fixes the issue, so would advise for that first!*

Just received great feedback/hint from Eric E Swanson (see here) -while applying the described workaround successfully  (great to know!). From his reply:

“…This problem happened to me when I used the Disk Cleanup utility and removed Old Windows installations and/or Temporary Windows Update files (not sure on the exact verbage, but it was part of the list when you click on System clean up)…”

I did a few tests on my own (yes, I had that problematic folder properly backed up, and a full OS partition image also, just in case) and…

Turns out a surprising operation that can cause the Windows Critical Service Failed boot BlueScreens is really…. Windows Disk Cleanup Tool…


Just tested and really something strange is happening with Disk Cleanup. First time I ran it, left the default few options (sorry didn’t proper screenshot that), confirm delete, wait a few seconds, nothing. Everything still the same on C:\Windows\System32\CatRoot\{F750E6C3-38EE-11D1-85E5-00C04FC295EE} 4.586 files from my last restore (note: these are driver signatures that Windows checks if drivers are properly signed)


Ok, I don’t give up easily…. 2nd run,this time selecting Clean System Files, then leaving the only default option checked, Temporary  Files. Also strange that it mentioned ~20GB of cleaning (that folder is around ~100MB total)


But this time a few files were actually removed from C:\Windows\System32\CatRoot\{F750E6C3-38EE-11D1-85E5-00C04FC295EE} . 


Ok a few files removed… strange, so ran it again, same options, selecting Clean System Files, then Temporary Files. Also strange that now seems to mark only ~15GB to “clean”. Swear probably it’s the last I use this tool…..


So, this time, after cleanup, these were the only files left: (67 files only!) Almost the entire driver signature folder completely removed:


So, testing the boot right? Back to the old boot BSOD/Critical Service Again (at least that makes sense!). Now much quicker to recover, as described in previous post, just pasted the files again from a backup folder (after disable boot option, drivers signature enforcement).

Boot again with the folder recovered, no more blue screens or issues with unsigned drivers!

Even strangest, tried several times after that, even with a few reboots, can’t seem to replicate it now using Disk Cleanup. Folder steady at the 4.586 files.

After all this, also strange than I got now ~5 GB (keeps changing?) yet to be cleaned no matter how many times I try. Meantime, I can confirm I have around more ~15GB free space on the win partition. What files has cleanup removed? Don’t have a clue and it’s kinda freaking me out….. tool from hell. Smile (which btw remind me the BOFH immortal words… “Well, let’s see, you have 4 Meg available" …)



Searching online there are several help requests regarding this kind of Blue Screen , and even a few mentioning Disk Cleanup as a possible cause. (see below)

Didn’t found any official/tek details info from msft , seems lacking proper awareness & follow-up from msft support teams honestly (yes, if not already, someone should really be looking into this).

How can such annoying, frustrating boot Blue Screen  keep appearing online and being so difficult for users getting proper solution beyond the typical- format & start again? (seems also something is lacking on the startup logs/troubleshoot process, are we not in the age of big data?…)

So, hope this helps,(helped two of us any way Smile )


Similar issues mentioned online

Reddit-Windows 10 Critical Service Failed BSOD reboot loop. Boot fine with driver signature enforcement disabled.
(mentions installing creators update as a fix, better one I would say)

All System32 drivers are suddenly unsigned in Windows 10
(thread where I posted the workaround and got the Disk Cleanup hint from Eric E Swanson )

Disk Cleanup causing Windows 10 to go into BSOD loop

Windows suddenly won’t boot, “CRITICAL_SERVICE_FAILED”

Windows could not load properly after disk cleanup

Windows 10: Disk Cleanup is causing a Blue Screen

OS is going to blue screen after disk cleanup


5 minutes to #DeepLearning on #Azure #DataScience VM with #Docker #NVidiaDigits #Caffe–CPU version

Quick post following previous one , for anyone who can’t have a GPU for any reason you can still use the code & Docker images below to do the same, but yes it will take a lot more time to train models. Sad smile

Started from Digits CPU Docker image here (amazing work with these Docker files by Kai Arulkumaran) and just added volume configuration for digits data & jobs.

So you can use, on Docker/Ubuntu :

docker run –rm –name digits-cpu -d -v $PWD/digits-data/:/data -v $PWD/digits-jobs:/jobs -p 5000:5000 rquintino/digits-cpu && \

docker exec -it digits-cpu python -m digits.download_data mnist /data/mnist


On Docker/Windows:

docker run –rm –name digits-cpu -d -v "%cd:\=/%/digits-data"/:/data -v "%cd:\=/%/digits-jobs":/jobs -p 5000:5000 rquintino/digits-cpu

start http://localhost:5000

docker exec -it digits-cpu python -m digits.download_data mnist /data/mnist

One issue you’ll probably have with docker windows data volumes is performance. Think there are some known issues regarding some operations on volumes on Docker Windows, which the mnist prepare script should be triggering (60k images).

CPU Train Performance

Using the GPU on the Azure Data Science VM NC series model full train for 30 epochs is around 1-2mins, using the CPU version like above I had to wait ~19 minutes. So 5 minutes won’t be enough!



Image docker hub/github




Recovering from Windows 10 boot Blue Screen, Critical Service Failed, Disable drivers signature enforcement, Unsigned Drivers

In case it helps someone, worked for me in a recent very annoying BSOD in my Windows 10
(instead of a full refresh or fresh install, don’t settle easily for that, usually try to dig a little bit and see what I can find…).

*update 2017-05-19, found this thread on reddit with a safer fix/workaround: seems installing the new Windows creators update fixes the issue, so would advise for that first!*

*update 2017-05-19, please read the part II for additional info and possible issue with Disk Cleanup tool: Disk Cleanup and Windows 10 boot Blue Screen / Critical Service Failed – Disable drivers signature enforcement, Unsigned Drivers *

Please note: It’s been stable and no problem with restarts for a few days now, but not saying it’s a permanent fix or better than a clean install. Will update if something changes. (probably something on my system is triggering this and will happen again)

My advice also before testing any kind of changes or emergency repairs, keep calm, don’t make it worst, backup the data you want safe before anything else.

My setup

  • Dual boot, default Win10 enterprise and an old Win81 legacy boot partition I still use occasionally
    (ex: when I get a recurring Blue Screen on boot !), no bitlocker
  • Separated Data drive, with bitlocker
  • Win10 Build 14393.1066 Version 1607
  • Single SSD, 3 main partitions


  • On restart and before my dual boot selection screen I get the Blue Screen,
    detail message is Critical Service Failed
  • Image result for critical service failed windows 10
  • Suspect this usually happens after major updates, I have the bad habit of never restart and always hibernate…
  • The system is bootable if you choose the “Disable drivers signature enforcement” on the troubleshoot / AdvancedOptions / Startup settings screens (usually option 7 when you restart)
  • Image result for Disable drivers signature enforcement
  • After restart with “Disable drivers signature enforcement” windows works pretty much as normal
  • But every restart you will get the same Blue Screen as this option is not permanent (nor advised), and I end up having to do two restarts to enable the option again, better than nothing but annoying
  • Running sigverif  tool (after booting with  “Disable drivers signature enforcement” to get Windows working) showed a huge number of “not signed” drivers??
  • image
  • in Event log (Application and Services Logs > Microsoft > Windows > CodeIntegrity > Operational I see a lot of errors when windows tries to load driver signature files needed, seems suddenly all drivers are being marked as not signed and Windows won’t allow it, except for enabling the “Disable drivers signature enforcement” boot option, also errors pointing to files I don’t have in C:\Windows\System32\CatRoot\{F750E6C3-38EE-11D1-85E5-00C04FC295EE}
  • image
  • Drivers then get marked as not signed! not good…
  • image
  • When compared to similar setup from another win10 same build, the number of files on my C:\Windows\System32\CatRoot\{F750E6C3-38EE-11D1-85E5-00C04FC295EE} is very low (~1600 vs ~6000 files in the working win10), only two files starting with M… on my folder?
  • image

What worked for me (use as is, as a last resource, no guarantees whatsoever, do your backups!):

After checking my win 10 build, got a zip with all the files in C:\Windows\System32\CatRoot\{F750E6C3-38EE-11D1-85E5-00C04FC295EE} from a “healthy and compatible donor” Smile (thx António) and pasted the missing ones on my system. Being cautious not to overwrite any file just in case and doing a backup of my folder (obviously!).

check the build numbers, *probably* they should match your win build version, ex 14393


Restart, now the boot selection appears, choose win10, everything working. sigverif tool now only complains about few files that seem not critical, previous Eventlog CodeIntegrity errors also clear.

Now, what I really have a hard time to accept is why do we contribute with so much data, diagnostic & logging information these days, and still no sign of minor “windows data intelligence” suggestions to help with a problem that for sure I’m not the only to experience…

Thx also to Pedro Sousa and José António Silva and our Help Desk for their tips & guidance.

Yet again I skipped that clean install! Winking smile 

Some references with similar problems

Critical_service_failed BSOD restart loop windows 10

All System32 drivers are suddenly unsigned in Windows 10

(Which reminds that one of these days I probably should share some thoughts on bitlocker, efs and …backups, do your backups! and be sure to test them!)


Some windows tools I really like & use, and you may not know about…

No! this is not another “all the best tools any windows developer should use”. There are plenty of other good resources on that (see below)… I won’t talk about fiddler, I won’t talk about notepad++, I won’t talk about reflector… you get the point. Smile

This post is about some tools I use, most of them daily and extremely frequently, but are not…  how to say? windows developer ”mainstream” kind of tools, or in other cases they’ve been so useful to me that I feel obliged in publicly saying “thank you” and just pass the word along.

I remember now doing my “hacked” techdays 2005 session, back then for example, fiddler had not the visibility it has today. In fact I discovered it on the day before the session I think, as the session was prepped with a rather “low featured” java http proxy (the only I found useful at the time, proxies were really not mainstream I think, who the hell would be interested in changing http requests on the fly? Smile what for?). In fact I think someone from Microsoft asked me if I really couldn’t found any other proxy…. with better looks and… were not…how to say this… Smile “java” based? ) . And so I did, googled deeper and my use of fiddler started there.


So, to the point,  here they are, I think most of these (great IMO) tools are still somehow in the “shadows”. And all of them survived my “quarantine cool tool period” witch is rather long, and I use them frequently  for several months, even years, now.


Prism HUD, from UtilHaven, free version available


Got it almost always on, it’s a rather great example of a proper simple “data intelligence” based tool. (now really, “business intelligence” doesn’t make much sense for me as a term… but that’s a “bedtime story” for another post)

When your cpu starts peaking you can immediately see which process is causing it, if your network usage spikes you know it. Configurable. Low on resources, I don’t performance benchmarks (eg: olap) without  it. Only disable it when presenting or taking screenshots. Now if all decision makers would have this kind of real-time feedback on their business… Smile


John’s Background Switcher, free, from John Conners


Just an amazing and feature rich background switcher. Love it. Best one I’ve seen. Always seeing different things on my background (some of them rather surprising Smile  sometimes)


AutoHotKey, Free

Anyone who likes code snippets should see this one. For example: I really don’t usually remember my professional mobile phone, when I need it I just type mtlm-  anywhere (in fact I had trouble writing this as it immediately replaced it Smile )

Fully customizable, some example scripts:
windows key+g-> run google
#g::Run www.google.com

my phone shortcut

my kind regards snippet
Kind Regards,
Rui Quintino


Pure Text

Great tool to strip html/rich text formatting. Pastes plain text. Use it a lot. Just press windows+v .

FireFox Copy Title

I really can’t possibly count how many times I’ve used this. Just right click any firefox page and select Copy Title, you’ll get this:

CopyTitle for Firefox


Quick Jump, from TechHit, not free but worth every $$ (unless off course someone remembers doing the same for free Smile )



Already mentioned it on my post.  Just press ctrl-shift-J and begin typing to get placed in your target windows folder. Works with most save & open file dialogs. (not with vs 2010 I’m afraid).


Outlook Add-On Clear Context, Free & Pro Edition


Ok, this not an unknown tool for sure, but still not very common between developers. I use it with my mail handling. If you’re being overload my email handling, just give it a try. You’ll get more time to code if you’re not dealing or searching email right?




Used from the first versions I think , just love it. Specially when combined with johns background switcher above. One click and I get back my beautiful and always fresh wallpaper!


Calibre e-book  management


Absolutely awesome tool to manage ebooks and a great companion to my beloved Kindle Smile .

Lots of features including book metadata retrieval, kindle connection, support for rss feeds & automatic delivery to kindle.

Just great!


CyberKiko FTPSync, Free & pro version

A great tool to synchronize files & folders with ftp servers. Used it already with great success! And Kristof is extremely responsive with support requests.


Jump To Folder, my little free Outlook  macro& form to speed search outlook folders


I know… but hey,  Scott Hanselman also put his cool baby app on his favorite tools page right? And I actually use it (as you can see in the screenshot ,  I even put a counter on itSmile )

Life Hacker

Yes, not a tool, but a great site that I review *every* single week. Some of the tools on this page I discovered on LifeHacker. Lots of interesting reading, being  cool tools one of them.

Final notes…

If you are still interested in “all the best tools” you can get, then be sure to check these links (sure many others exist):

Scott Hanselman – Scott Hanselman’s 2009 Ultimate Developer and Power Users Tool List for Windows

What is your best list of ‘must have’ development tools? — HTMLCoderHelper.com

(ps-some of the tools I used when writing this post include  copy title, quick jump, pure text,  jump to folder…aside from screenshot usage )