As far as I remember it is Windows OS application crash assistant or something like that.
- Make sure that you run the injector in Administrator mode.
- Try using sinJect (works for me Windows 7 x64)
- Not sure if its related but open properties of Vindictus.exe and in the compatibility tab check "Disable desktop composition"
- Also try disabling antivirus and firewall or add "vindictus hack" folder to the exeptions
Let us know if any of this helped you