I have the following problems :

Many of my pages when they get crawled by Sistrix get marked with a 404 code. But in fact these are pages which have been deleted like 3 years ago. Why do they still get indexed and how can I remove them even they don't exist anymore ?

And there are URL's marked with a 404 even they exist. This is one example : https://www.hanspeterkruesi.com/members/files/category/5-rock-guitar/

Thanks for the help in forward.

Hanspeter

You would need to speak to them regarding that. We cannot answer why they are trying to index pages that dont exist