Character Transfer Problem

Hi

I am attempting to transfer my character from Mannoroth to Kil'Jaeden using the 'Paid Character Transfer' option. They are both PvP realms. I have nothing in my inbox, and I don't think I have any mail incoming, and definitely none outgoing. When I attempt to click 'Continue' after picking my target realm for the character, a page comes up titled "Error Encountered', and the error message simply says "An error has occurred', without telling me how to fix it. Is this a problem on my end? Thanks