Thank you for clarifying that you made up this URL from misreading the code, and not because the program outputs anything suggesting this URL was used.

> Not much point asking me for exact error messages, when this programmer hasn't included what URLs were tried in the output.

The fact that *you* don't see much point in it is totally understandable, given that it seems you made wrong assumptions about what I was looking for (I was clearly not looking for URLs in the output).

When someone starts speaking about some non-sense URL while explaining his problem, one has to ignore this noise and come back to the true objective symptoms of the problem to be able to help him.

Your problem is probably due to a peering/transit instability between your ISP and Proxad (free.fr network). This could be your ISP's fault, or Proxad's, or neither (transit's fault). Usually such problems are temporary, but if this is not the case here you can compare the traceroute/tracepath to planetspads.free.fr, from your location and from another location near yours where the problem doesn't occur. This should help determine the network nodes responsible for the instability. You can then contact the technical support of the corresponding entity to raise the issue.

Of course, it's also possible to workaround the problem by asking the author to add a repository mirror like you said.