From Intense Ragnarok Online Wiki
Patching kRO and kRO RE
Most users have difficulty patching kRO and kRO RE. The Image will show you which icon you have to click or RUN as administrator to patch your kRO and kRO RE! Please note we use kRO and kRO RE as base grf (resource files) for running IntenseRO. So Patching both is really necessary.
Please make sure you are not running IntenseRO while patching else it will fail.