Upgrade to Professional is not working

Hi - I have just paid for the upgrade to Pro and it has not gone well !! I get the message as in the attached screenshot. Nothing happens if I retry and if I ignore then its carries on and appears OK. It appears to work but it is in FREE mode only.

Any suggestions would be helpful please.

Capture.JPG

It's a common issue and is caused by CCleaner still running in the background, as CCleaner64.exe is still running the upgrade can't replace it.

Try the steps given here:

https://forum.piriform.com/topic/53111-fail-to-install-ccleaner-pro-v5516939/?tab=comments#comment-302097