Nostalrius Begins - Quality wow vanilla realm (1.12)

I downloaded the alternative one from the post on the first page , i then dl winrar and extracted to my desktop then created a folder in my programs and moved it all there. Changed the realm list and now when i click the wow.exe i get an error :

ERROR #121 (0x85100079) Version Mismatch
Program: C:\Program Files (x86)\Classic Wow\WoW.exe

I've seen other people mention this problem but haven't seen any replies or posts with solutions.

Can anyone help?

The download could be corrupted. Try right clicking the wow.exe and run as administrator.

You might have to try another download.