Thanks - I have done as you suggest. I did not disable Windows Defender when I did the scan as I think Malwarebytes is compatible with Defender? Anyway, it detected 4 threats from PUPs:
C:\Program Files (x86...\bin\SPVC32Loader.dll
C:\Program Files(x86...\bin\SPVC64Loader.dll
HKLM\SYSTEM\CURRE...ERVICES\CltMngSvc
C:\Program Files (x86...ain\bin\CltMngSvc.exe
I have removed these. Nothing found in relation to CAFADEBUG, which is still there and still updating when log out and switch off.
I guess all is ok then.....for now anyway?