Hierarchy Manager detected that site code "%1" is already in use by existing site "%2".%12 Possible cause: Site "%3" is using ...

%11Hierarchy Manager detected that site code "%1" is already in use by existing site "%2".%12

Possible cause: Site "%3" is using the same site code as another site.
Solution: Each site must have a unique site code. Deinstall one of these sites and reinstall it using a unique site code.%0