cannot start/open ccleaner anymore Windows 10 20H2

[Epic]

I can not open/start ccleaner any more, even tried to update to current realse 5.74 but still nothing.

Running Windows 10 x64 Pro -up2date- version 20H2 build 19042.572 (Windows Feauture Experience Pack 120.2212.31.0), even without Windows Defender and Sophos antivirus (both disabled), nothing happens.

When I try to open, it seems like it crashes immediately, no ccleaner window or whatever, can't even see the service starting in task manager (it does seem to start for about a second and then it's gone). Tried ccleander.exe /debug & ccleaner64.exe /debug but nothing, but this is expected since ccleaner just won't start at all.

I tried looking into eventvwr.msc - windows logs - apps and there I see event 1001 : APPCRASH (but without info), tried  uninstall, tried portable, removed ccleaner reg.keys from windows registry, but I cannot seem to fix it :'( and I'm kind off running out of ideas right now.

With kind regards

[hazelnut]

Can I just ask if you have tried the slim build from here? (last on in list)

https://www.ccleaner.com/ccleaner/builds

Also have you tried updating Windows to 19042.630 ?

You should not have to disable your Anti-virus to install CCleaner. Also Defender will disable itself anyway when you install another AV.

[Epic]

2 minutes ago, hazelnut said:

Can I just ask if you have tried the slim build from here? (last on in list)

https://www.ccleaner.com/ccleaner/builds

Also have you tried updating Windows to 19042.630 ?

You should not have to disable your Anti-virus to install CCleaner. Also Defender will disable itself anyway when you install another AV.

Also tried slim, same result

Can't download that version yet, Windows Update is up to date (at least that is the message it gives me at this moment)

Never had these disabled indeed, but for testing purposes I just did, with no result...

[Guest MeganCCleaner]

Hi @Epic Would you be willing to see if CCleaner will open when using Windows in Safe Mode, or Safe Mode with Networking?

[Epic]

13 minutes ago, MeganCCleaner said:

Hi @Epic Would you be willing to see if CCleaner will open when using Windows in Safe Mode, or Safe Mode with Networking?

aaah forgot about that one, yes I'll try...

[Epic]

2 hours ago, MeganCCleaner said:

Hi @Epic Would you be willing to see if CCleaner will open when using Windows in Safe Mode, or Safe Mode with Networking?

this does help, now I can open it, but not in my normal account. I still think it has something to do with microsoft defender / security center though. Because when I download ccleaner with edge it does complain about the file and if I whish to keep it anyway, I do think this does prevent ccleaner from opening. I removed Sophos because of testing purposes but that does not make any difference. I do not have problems with any other software so that is why I think Windows is somehow blocking ccleaner. When I try another account on my workstation I do have exactly the same problem, ccleaner will not open.

[nero75]

Same Problem in here. Same win10 build, same issue.

[katlani]

It's a well known phenomenon that CCleaner is being flagged by Windows security.

https://www.digitaltrends.com/computing/microsoft-defender-ccleaner-unwanted-application/#:~:text=Microsoft's Windows 10 operating system,as first reported by Bleepingcomputer.

Might also be worth taking a look here:

https://support.piriform.com/hc/en-us/articles/360041626791-How-do-I-Stop-Windows-10-from-blocking-my-installation-of-CCleaner-

[Epic]

2 hours ago, katlani said:

It's a well known phenomenon that CCleaner is being flagged by Windows security.

https://www.digitaltrends.com/computing/microsoft-defender-ccleaner-unwanted-application/#:~:text=Microsoft's Windows 10 operating system,as first reported by Bleepingcomputer.

Might also be worth taking a look here:

https://support.piriform.com/hc/en-us/articles/360041626791-How-do-I-Stop-Windows-10-from-blocking-my-installation-of-CCleaner-

yeah I know, but there's no solution there...

=> I'm allowed to install outside the Microsoft Store and i'm not in 'S mode', I disabled defender (as stated earlier) and also tries the CC-slim version...

[nukecad]

Just to note that we have had 2 users who needed to do a restart of 20H2 (Windows 2004) before CCleaner 5.74 would install properly for them.

I'm not sure why that should be, it's not something that is normally needed.

If you haven't done a Windows restart (not a shutdown/reboot) for a while, and especially if you normally sleep/hibenate, then a Windows restart may be worth a try.

PS. I'm begining to suspect that at least some of these CCleaner can't run or can't install issues for certain machines may have been caused by last weeks Windows Patch Tuesday updates.
 

[Epic]

5 hours ago, nukecad said:

Just to note that we have had 2 users who needed to do a restart of 20H2 (Windows 2004) before CCleaner 5.74 would install properly for them.

I'm not sure why that should be, it's not something that is normally needed.

If you haven't done a Windows restart (not a shutdown/reboot) for a while, and especially if you normally sleep/hibenate, then a Windows restart may be worth a try.

PS. I'm begining to suspect that at least some of these CCleaner can't run or can't install issues for certain machines may have been caused by last weeks Windows Patch Tuesday updates.
 

I did reboot more than once, u installed ccleaner, remover all possible reg entries, tried reinstalling ccleaner, ccleaner slim, ccleaner portable but no luck. It just won't open anymore

[Epic]

Just to update current status as is, I have'nt got it pinpoint yet. It will work in safe mode but not in any other way (tried different accounts)... 

It always worked but now it does not anymore, my best guess is still that something in Win10 does'nt approve ccleaner anymore / at this time

[stbufraba]

On 18/11/2020 at 18:30, nukecad said:

PS. I'm begining to suspect that at least some of these CCleaner can't run or can't install issues for certain machines may have been caused by last weeks Windows Patch Tuesday updates.

You could be right.

Latest CCleaner is not even starting anymore on my Windows 10 Pro 2H2 build (19042.662).

So I deinstalled CCleaner and rebooted to install it again. To my surprise the installer does not work. Slim installer does. But CCleaner will not start anymore.

Edited December 3, 2020 by stbufraba

[hazelnut]

@stbufraba

Could you have a read here in your other thread please

https://community.ccleaner.com/topic/59532-windows-10-vern-20h2-190420630-will-not-install-ccleaner/?tab=comments#comment-325353

 

[Epic]

I don't have install problems, just still can't open/start CCleaner anymore (disabled anti virus etcetc, as stated earlier)

[Dave CCleaner]

On 18/11/2020 at 08:06, katlani said:

It's a well known phenomenon that CCleaner is being flagged by Windows security.

As with so many things relating to CCleaner, there's a grain of truth to that story heavily wrapped in several layers of myth. There was an issue back in July with Microsoft taking a dislike to the installer (although not CCleaner itself) which was solved two weeks later with CCleaner 5.70.  Any "news" about CCleaner tends to turn into "olds" pretty quickly  

On 22/11/2020 at 00:29, Epic said:

something in Win10 does'nt approve ccleaner anymore / at this time

The only versions of CCleaner that are "hard blocked" by Microsoft from running on Windows 10 due to compatibility issues are versions prior to CC5.46.

There does not seem to be an issue with Windows 10 20H2, per se: 5.74 was tested against 20H2 prior to release and I upgraded myself to 20H2 a couple of weeks ago to see for myself how 5.74 update scenarios would work and have not seen any changes. 

That said, there are a couple of releases planned for December that just focus on minor tweaks and bug fixes - predominantly ones that impact corner-cases and small audiences - so it is possible that any issues that may be impacting your specific system configuration may be mopped up with those.  But in the meantime, any additional information that impacted customers are able to provide regarding their individual setups would be gratefully received.

On 18/11/2020 at 17:30, nukecad said:

Just to note that we have had 2 users who needed to do a restart of 20H2 (Windows 2004) before CCleaner 5.74 would install properly for them

Indeed, I have had 40 years of with home computers and "have you tried switching it off and back on again" is still a tried and tested solution to most problems.  

[Epic]

Not much to add as what's already stated I'm afraid, CCleaner just won't open... Install, uninstall, re-install is no problem, but when I try to open CCleaner, nothing happens at all. 

Everything worked fine before Windows 10 update to latest 20H2, I disabled Defender / Microsoft security and Sophos (anti4us) but without result (no solution). The tricky part is that when I start Windows in 'safe mode', there's no problem running CCleaner. But in 'normal mode', nothing happens. I can try other login account or a new account, but with the same outcome, CCleaner just won't start/open. 

Event logs don't show something weird, except APPCRASH (event 1001), but with no extra info what so ever. 

Still fiddling with this from time to time, but nothing yet.

[hazelnut]

Because everything works ok with CCleaner in safe mode it points to the fact that it is something running in real time that is causing this for you.

My money is on Sophos (which doesn't run in real time) Only way you will know for sure is to uninstall it, restart twice and then try running CCleaner.

[Epic]

On 07/12/2020 at 06:00, hazelnut said:

Because everything works ok with CCleaner in safe mode it points to the fact that it is something running in real time that is causing this for you.

My money is on Sophos (which doesn't run in real time) Only way you will know for sure is to uninstall it, restart twice and then try running CCleaner.

nope it's not, like I stated earlier, disabled this (and verified no services or what so ever were running)

[Epic]

"FIXED IT" (...well sort of...)

-> I was misssing the CCleanerSkipUAC scheduled task

Exported this from another computer, imported it in my troubled workstation, restarted and things are doing again as they're supposed too...

Weirdest thing is in my opinion is that multiple re-installs did not fix this missing scheduled task

edit: BUT only auto.start CCleaner at logon and then I can open it, but when I close CCleaner and then try to re-open, again nothing...really weird... (and after 2nd reboot this also doesn't help though)

PS. when I run this service manually I get this errorcode in return: 0xC0000005 (and CCleaner.exe won't open)

Edited December 8, 2020 by Epic
see 'edit: + PS.'

[Guest MeganCCleaner]

On 06/12/2020 at 17:43, Epic said:

Not much to add as what's already stated I'm afraid, CCleaner just won't open... Install, uninstall, re-install is no problem, but when I try to open CCleaner, nothing happens at all. 

Everything worked fine before Windows 10 update to latest 20H2, I disabled Defender / Microsoft security and Sophos (anti4us) but without result (no solution). The tricky part is that when I start Windows in 'safe mode', there's no problem running CCleaner. But in 'normal mode', nothing happens. I can try other login account or a new account, but with the same outcome, CCleaner just won't start/open. 

Event logs don't show something weird, except APPCRASH (event 1001), but with no extra info what so ever. 

Still fiddling with this from time to time, but nothing yet.

Hi @Epic Considering how CCleaner does open in Safe Mode, you may want to perform a 'clean-boot' in Windows, using a process of elimination to see if you can pinpoint what prevents CCleaner from being able to open in the normal mode of Windows.

Instructions on how to do this can be found at https://www.windowscentral.com/how-clean-boot-windows-10

[Epic]

4 hours ago, MeganCCleaner said:

Hi @Epic Considering how CCleaner does open in Safe Mode, you may want to perform a 'clean-boot' in Windows, using a process of elimination to see if you can pinpoint what prevents CCleaner from being able to open in the normal mode of Windows.

Instructions on how to do this can be found at https://www.windowscentral.com/how-clean-boot-windows-10

Might be a good idea indeed, will try and see what might come up, thanks for pointing this out. 

[Epic]

For archive purposes, uninstalling Citrix receiver fixed the problem. Not a real solution but after a reboot CCleaner worked again. 

Somehow my Citrix receiver and CC don't play well together, if I reinstall the Citrix receiver same thing happens again, CC won't work/open at all. 

[nukecad]

Good investigating to eventually track down what the issue was @Epic.

It may be clashing because Citrix Receiver reached end of maintenace on Sep 30th 2020 (about a month before you first encountered the issue with a new CCleaner version), and reached end of life on 31st Dec 2020, - so it is no longer maintained or updated.
https://support.citrix.com/article/CTX280728

It has been replaced by Citrix Workspace app for Windows.
Maybe try that and see if the issue is solved?
 

[Epic]

3 hours ago, nukecad said:

Good investigating to eventually track down what the issue was @Epic.

It may be clashing because Citrix Receiver reached end of maintenace on Sep 30th 2020 (about a month before you first encountered the issue with a new CCleaner version), and reached end of life on 31st Dec 2020, - so it is no longer maintained or updated.
https://support.citrix.com/article/CTX280728

It has been replaced by Citrix Workspace app for Windows.
Maybe try that and see if the issue is solved?
 

Yeah we're using a completely different way of Citrix (remote desktop concept) and with that combination there's no problem. I do have to uninstall the old/previous receiver. 

Maybe it can help other in a near future