If the ArcWeb Services toolbar is installed before MOLE, the following error may occur when trying to install MOLE:
"Military Overlay Editor requires 9.1 or higher version of ArcGIS Desktop, ArcGIS Engine Runtime, ArcReader, ArcIMS ArcMap Server or ArcGIS Server to continue."
This happens when the ArcWeb services toolbar version 1.1 is installed prior to installing MOLE 9.1. The installation of the ArcWeb toolbar is replacing the ArcGIS 9.1 coreRuntime hives with 9.0 characters. When MOLE runs, it expects ArcGIS 9.0 is installed.
The steps below include making changes to essential parts of your operating system. It is recommended you backup your operating system and files, including the registry, before proceeding. Consult with a qualified computer systems professional, if necessary. ESRI cannot guarantee results from incorrect modifications while following these instructions. Therefore, use caution and proceed at your own risk.