If I try to launch the game client directly via "C:\Program Files (x86)\Zenimax Online\The Elder Scrolls Online PTS\game\client\eso64.exe", I get a fullscreen black background with the following error dialog on PTS:


I don't get the same error on live. The following command succeeds:
"C:\Program Files (x86)\Zenimax Online\The Elder Scrolls Online\game\client\eso64.exe"

I noticed that when I load the live client, the Documents\Elder Scrolls Online\live\UserSettings.txt gets updated with the current date/time, but the same doesn't happen with the PTS client to Documents\Elder Scrolls Online\pts\UserSettings.txt. Instead, it creates an empty folder structure in Documents\Elder Scrolls Online\rc.

This is after the game client fully patched with v7.3.1. The PTS client loads fine from the Bethesda launcher, and it updates the Documents\Elder Scrolls Online\pts directory.