WOW51900223 Error Solution:
- Be subscribed, otherwise you can’t create a new PTR account
- On the website, go to Games & Subscriptions
- Scroll down to Starter Editions & Public Test Regions
- Create PTR account
- Launch the PTR, select the new account, or try each WoW1, WoW2, etc
You can now see the 4 realms, not just the 2 red beta realms