Attach your log. ( http://www.thebuddyforum.com/honorbuddy-forum/guides/9859-how-attach-your-hb-log-file-pictures.html )I'm having the same issue and I followed these instructions all the way. Using W7.
So I'm just gonna type out what I did so you can tell me if I at some point did anything wrong.
1. downloaded latest version of hb
2. extracted from the rar to new folder on desktop named Honorbuddy
3. started wow and logged into my character
4. ran around for abit before i started hb as admin
5. type in my key
So after this I get the message:
[23:52:08:814] Logging in...
[23:52:09:305]
[23:52:09:744] -------------------------------
[23:52:09:745] You have not selected a valid instance of WoW to attach to!
[23:52:09:745] Please restart Honorbuddy and choose a valid instance of WoW to use Honorbuddy with!
[23:52:09:745] This version of Honorbuddy only supports WoW Build #15050
[23:52:09:745] You are currently on build #0
[23:52:09:745] -------------------------------
[23:52:12:895] Honorbuddy is up-to-date