I'm having the exact same issue. So far I tried with two different versions, both with the same result. version 20338 (most recent version from bnet): 7/29 13:47:41.526 Login program=WoW platform=Win locale=enUS
7/29 13:47:41.615 Component WoW.Win.20338
7/29 13:47:41.671 Component WoW.base.20182
7/29 13:47:41.837 Battle.net is Component Bnet.Win.37165
7/29 13:47:41.908 LOGIN: state: LOGIN_STATE_CONNECTING result: LOGIN_OK
7/29 13:47:41.947 Connecting to 127.0.0.1:1119
7/29 13:47:42.019 LOGIN: state: LOGIN_STATE_FAILED result: LOGIN_BADVERSION
7/29 13:47:42.056 Disconnected from 127.0.0.1
7/29 13:47:42.143 Client initiated Disconnect from 127.0.0.1
7/29 13:47:42.206 LOGIN: state: LOGIN_STATE_FAILED result: LOGIN_BADVERSION
7/29 13:47:42.306 Login program=WoW platform=Win locale=enUS
7/29 13:47:42.377 Component WoW.Win.20338
7/29 13:47:42.407 Component WoW.base.20182
7/29 13:47:42.436 Battle.net is Component Bnet.Win.37165version 20182 (same version as server): 7/29 13:57:16.016 Login program=WoW platform=Win locale=enUS
7/29 13:57:16.050 Component WoW.Win.20182
7/29 13:57:16.081 Component WoW.base.20182
7/29 13:57:16.142 Battle.net is Component Bnet.Win.37165
7/29 13:57:16.170 LOGIN: state: LOGIN_STATE_CONNECTING result: LOGIN_OK
7/29 13:57:16.196 Connecting to 127.0.0.1:1119
7/29 13:57:16.240 LOGIN: state: LOGIN_STATE_FAILED result: LOGIN_BADVERSION
7/29 13:57:16.261 Disconnected from 127.0.0.1
7/29 13:57:16.293 Client initiated Disconnect from 127.0.0.1
7/29 13:57:16.319 LOGIN: state: LOGIN_STATE_FAILED result: LOGIN_BADVERSION
7/29 13:57:16.348 Login program=WoW platform=Win locale=enUS
7/29 13:57:16.372 Component WoW.Win.20182
7/29 13:57:16.403 Component WoW.base.20182
7/29 13:57:16.429 Battle.net is Component Bnet.Win.37165 I have even tried 32 and 64 bit versions for both the client and server... nothing!