DOC4000 allows you to use custom images in the DOC4000 web interface. In previous versions, these images were stored in the InstallPath/Images folder and the ig_common virtual directory was defined for this folder location. These images are now stored in the InstallPath/Images/old_common folder and the virtual directory is no longer defined or used.
If you have missing images after you upgrade DOC4000, copy your image files from the InstallPath/Images folder to the InstallPath/Images/old_common folder.