My site has recently started to experience pop up ads that appear after a few moments

I think these are malicious

What's the process for fixing it please?

(I've downloaded all the core files from my invision account and uploaded them over the top of the existing ones on my server, gone to the upgrade but it says there's nothing to upgrade)

Anything else I need to do?

There is no clear answer to this, as it depends where they are coming from. The only advise we can give from a software perspective is

• Ensure you are on a latest release

• Replace all files with a fresh set from stock

• Check nothing has been added to conf_global.php or constants.php

• Revert to a default unaltered theme

• Remove any 3rd party items

5 hours ago, Sheffielder said:

My site has recently started to experience pop up ads that appear after a few moments

I think these are malicious

What's the process for fixing it please?

(I've downloaded all the core files from my invision account and uploaded them over the top of the existing ones on my server, gone to the upgrade but it says there's nothing to upgrade)

Anything else I need to do?

Additionally, I would contact my host as well if I were you, and ask them to check the raw access logs if they can see how those malicious adds were inserted in your forum in the first place.

Are you using the latest version of Ipb? If not, it would be best to upgrade your forum a.s.a.p. Have you got other scripts running in your server, such as Wordpress for example, and if you do are you using their latest versions?