Hello @Ralph Seichter,
what do you mean by "mutually exclusive"?
As for the tools I mentioned, it was just an example.
Are you telling me I can't solve this problem?


Hello @garic,
thanks for this answer, it made me understand some things. But I don't think I understand everything you suggest to me.

Are you suggesting me how to make the link uncrawlable, but how to block direct access?

For example, if the user downloads the file, then goes to the download history, sees the url, copies it and re-downloads the file. How can I prevent this from happening?

Maybe you've already given me the solution, but not being an expert, i need more details if it's not a problem, thanks.

I found this stackoverflow topic that is interesting:
https://stackoverflow.com/questions/9756837/prevent-html5-video-from-being-downloaded-right-click-saved

Read the @Tzshand answer modified by @Timo Schwarzer with 28 positive votes, basically it's what I would like to do, but in my case they are pdf files and I use Nginx not Apache.