I have on successive scans found the same detections recurring. I had selected in Preferences the option, Move to quarantine Folder. Does Clamwin set up a quarantine folder on installation?

Yes, the quarantine folder is set up in the installation. The quarantine folder is a sub-folder in the ClamWin data folder. The location of the data folder is mentioned in the information in File Locations tab. The quarantine and database are both separate folders under the data folder.

There may be a recurring virus with a registry entry that re-installs it upon quarantine removal. If that is the case, if you have Windows XP or a newer version, I suggest you get Malwarebytes free Antirootkit (MBAR), put it on your desktop, update it, and do a scan. If nothing is found, get into Windows Safe Mode (F8 repeatedly upon bootup--select Safe Mode With Networking) and scan with MBAR. Plan B is to make a Microsoft Windows Defender Offline USB boot disk (from https://windows.microsoft.com/en-us/windows/what-is-windows-defender-offline), boot up with it, and do a scan.

Regards,