GetDirectory & CCurlFile errors

I am using kodi 17.3 on xenialpup64.

Here is the logfile: paste.ee log

ERROR: CCurlFile::Open failed with code 503 for http://mirrors.kodi.tv/addons/krypton/se…0.3.23.zip

And:

ERROR: GetDirectory – Error getting
ERROR: Previous line repeats 5 times.

What could cause these bugs.

Not blaming kodi 17.3, but blaming xenialpup64.

Just trying to figure out how to improve xenialpup64, so it doesn’t produce these errors.