When you tried to access the Express Tools on the toolbar, they didn't work and displayed question mark icons. The Express Tools commands didn't work at the Command prompt.
This problem occurs when you load the Express Tools menu file (acetmain.cui), but the Express Tools have not been installed on the system. The following solution explains how to install the Express Tools:
After the Express Tools installation, the question mark icons may remain on the toolbar. The acetmain.mnr file is responsible for the bitmaps of the toolbars. To remove the question mark icons delete the acetmain.mnr file. The next time you launch the application, the icons will be recompiled and they will appear correctly on the toolbar.
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