Silent installation is only supported in Nmap OEM - https://nmap.org/oem/ ???

[TonyCzar]

This error message just started popping up.  Uninstalled and reinstalled CCleaner, but no bueno.  Any wisdom appreciated.

[nukecad]

Nmap is a Network Mapping tool.
Is this a computer on a company network? Or maybe a large home network?

Nmap isn't installed in Windows as standard, it's a tool that has to be downloaded and installed.
(It may get installed as part of a Network Management application).

From your screenshot that's the software updater section of Health Check, so it's trying to update Nmap but Nmap isn't letting it.

Try using Tools>Software Updater to see more information, see if it finds Nmap as an application to be updated and what version it says you currently have.
(You will/should get the same error if you then try to update it).

There have been issues in the past with the Software Updater giving the wrong version number for Nmap and so trying to update it when no update is needed.

However Nmap did have an update recently, to v7.93, but you may have to update it yourself outside of CCleaner.
https://nmap.org/changelog#7.93

If you don't want to update it then you can either:

1. Use Custom Clean not Health Check. Custom Clean does not automatically run Software Updater.
2. Click OK and ignore that warning. It should just leave Nmap alone, but you will keep getting that warning next time.
3. Disconnect from the internet when running Health Check. That will disable/prevent the Software Updater running in Health Check.

Using Custom Clean is usually the better option of the 3, it also give you much more control over what is or isn't cleaned.

You can set Custom Clean to be the default that CCleaner shows you, Options>Settings>CCleaner Home Screen.

[TonyCzar]

Thanks nukecad, you solved my problem.  In fact I had installed a network mapping tool some months ago just because it was free and I was playing.   But I had no need for it and uninstalled it.  Your post taught me that I also needed to unistall the Nmap programs.  I've done that and now no longer get that error message.  Grazie mille.

[nukecad]

That's good then.

You may still want to consider using Custom Clean rather than Health Check, most more advanced users do for the extra control that it gives.