I ran into a problem when we moved to Wabbajack the other night, I could not set Wabbajack as a guest or as my home campaign. After searching around here is what I found out.
If you have an alt in another alliance they can be autoset to a random PVP server, even if they are not level 10. My level 8 nightblade had someone been set to Wabbajack, which prevents your joining that campaign on any other alliance. I deleted my nightblade and it fixed this issue. Just an FYI.
