Could you define the nature of the pop-up? Is it in the browser? On the desktop? through certain applications? When did the issue start happening? (Please answer these before continuing the read)
Since I am not certain about how it manifests, I can only offer a general thorough PC clean-up. The following steps should help you remove the issues, but make sure to post MBAM and ADW logs after scans.
For this, I would recommend restarting your Windows to "Safe mode with Networking"
1. Use RKill to kill any malicious processes
2. Check your installed programs for any suspicious ones and remove if found
3. If the pop-ups are in browser, open your browser extensions/add-ons and remove ones you do not recognize (Also recommended to reset your browser or use browser specific cleanup tool)
4. Scan with anti-virus software of your choice or just use Windows Defender (If you have Windows 10), It works great in most scenarios.
5. Scan your PC with Malwarebytes, AdwCleaner, and Hitman Pro. Multiple anti-malware solutions will confirm the clean-up
6. Use CCleaner to clean registry and cached files.
7. Restart your PC and do an additional anti-malware scan to check if the issue has been removed.
Let me know if the tips help, but as mentioned, answering the questions will help immensely. If the problem persists, let me know, we shall see what we can do about it.