ICE48 checks for directories that are hard-coded to local paths. You will usually encounter this behavior when creating a Property Based Folder based on a property initialized in the Install Parameters page. In this case, ICE48 would issue the following warning:
Directory ' <directory_name>' appears to be hardcoded in the property table to a local drive.
The solution to this is to initialize the property from the UI using Set installer property value control event or by using the Set installer property custom action before CostInitialize standard action. After making sure the property is properly initialized, you can safely remove it from the Install Parameters page. The ICE48 warning should now be gone.