Possible issue with Windows 10 using CCleaner 6

[Msheff]

I had to uninstall CCleaner because it was interfering with Windows 10: during startup, a message window would appear asking me to give permission for Piriform. When I clicked "Yes", the screen went completely black, with only the mouse showing. This message window never appeared when I was running Windows 8.1

After installing Windows 10, this message window always appears. I always clicked "yes" and had no problems until about 10 days after installing Windows 10, when the above problem happened. On reboot, I clicked "No", but the screen still went black. Rebooted again, and again clicked "No". This time, success. My usual desktop appeared and was stable.

A call to Fujitsu tech support generated the suggestion that I uninstall CCleaner, which I have done. There has been no repeat of the problem, which suggests CCleaner was causing it.

[nukecad]

Like this? (Yours is probably white not black).

That's the Windows 10 User Account Control (UAC), it will be showing during Startup because your CCleaner is set to start when you start Windows.
(There are a couple of things in CCleaner that could do that).

You'll also see it when you launch certain other apps, but not all apps.
It's usually for those apps that can change things in the system, (eg. CCleaner can delete temporary system files).

You can prevent Windows from showing that UAC warning for CCleaner.
To do that reinstall CCleaner and open it.
If you get that UAC warning when opening it, click Yes.
Once CCleaner is open go to Options>Advanced and tick the box for 'Skip User Account Control Warning'.
I'd also tick the one above it 'Save all settings to INI file'.
Close CCleaner.

Open CCleaner again and it should now open without giving you that warning.
The same should apply when you start Windows, no more CCleaner warning.

If that doesn't work, or if you want to know more about why your CCleaner is staring with Windows, then please come back.

.

[Msheff]

Thanks, nukecad.  The problem was after clicking Yes (or No!), my whole screen went black (except for the mouse pointer) and I could not access anything at all. Had to force quit each time.

The problem went away after uninstalling CCleaner.

I have re-installed CCleaner Pro (v. 6.07.10191 64-bit) and the black screen problem has not recurred.

I checked the Options>Advanced and found "Skip User Account Control Warning" was already ticked. I ticked "Save all settings to INI file" as you suggested, tho I have no idea what that means ;-) You sound like you know what you're talking about so I'll take your suggestion.

Thanks again.

[nukecad]

Good to hear that it's now working as it should after a reinstall. (I guess something went wrong with the previous install?)

Saving your settings to an ini file simply saves them to a 'CCleaner.ini file in in the CCleaner folder on your hard drive as well as in the Windows registry.
You can then make a backup of that file and put it back if you ever want/need to.
CCleaner will use the ini file, if there is one, in preference to the registry and will alter the registry to suit.

I do that frequently after I've been changing my settings to help answer a query on this forum, I use my ini backup to put my own settings back.
It's also useful/used by the Portable CCleaner version that doesn't save settings to the registry because it's for use with different machines.

Other INI files can also be used to add extra cleaning functions to Custom Clean, eg. so that it can clean apps that aren't included the regular listings.
The one used most for doing that is the 'Winapp2.ini'.
Winapp2 is semi-official, in that it is written and maintained by users and not by Piriform themselves, but it is approved by Piriform and has it's own section on this forum.

For general information on CCleaner and ini files see: https://support.piriform.com/hc/en-us/articles/360047940232-What-do-CCleaner-for-Windows-s-INI-files-do-

For more info on Winapp2.ini see: https://community.ccleaner.com/topic/32310-winapp2ini-additions/#comment-175835