I see others are having the same issue. I am playing through the regular client, not STEAM, and I am unable to login to ESO at all. I even tried destroying the launcher data file.

This problem is so bad that I can't uninstall the game, or run a new copy of the installation program as both are giving me the "unable to load skin" error.

If anyone finds a solution, I'd appreciate knowing about it. Perhaps I missed it somewhere, but it seems others are stuck as well.