"Secure PC Cleaner" Pop-Up on Google - How to Delete?

Sebastian, In future please refrain from carrying out multiple topic postings on the same subject! You won't obtain an answer to your query any faster!. Also please try to keep the whole conversation in one question/thread to speed up any resolution. Please see your other posting (https://support.avg.com/answers?id=906b0000000Dc5bAAC).
AVG Guru

I get a pop-up on my Google main page that suggests I use "Secure PC Cleaner" - that won't go away. I assume this is an example of "adware"? If it was malicious, I assume that AVG would have deleted it automatically, but it hasn't. How do I get rid of it? It is very annoying. I haven't downloaded anything, as far as I can recall.

Sebastian, In future please refrain from carrying out multiple topic postings on the same subject! You won't obtain an answer to your query any faster!. Also please try to keep the whole conversation in one question/thread to speed up any resolution. Please see your other posting (https://support.avg.com/answers?id=906b0000000Dc5bAAC).
AVG Guru