One recipe to fix all...
1. Move wow folder to root of c: drive (ex.: C:\wow)
2. Delete cache and patches: 5, W, X and Z in Data and 6, A, B an C in Data\enGB
3. While your client is closed... In your realmlist.wtf, add a new line to it:
SET realmName "Redemption"
4. Start Launcher as Admin
Also if you are still having connection issues you may want to temporarily turn off your firewall and add the wow folder to the list of exceptions of your anti-virus.
Let me know if it doesn't work.
Architect of Disruption since 1995