malware – How to get rid of software trying to automatically connect to

I use MalwareBytes and my machine could not connect to the website I can not say which program wanted to access this site in the background (I did not go on purpose).

Regular scanning with Windows malware detection and MalwareBytes does not show infected files.

I understand that some tools claim to be able to get rid of it, but I'm not sure I can trust these tools!

How can I determine the cause of the connection to this site in the background?