A dialog box does not appear to be opening?
Sometimes a dialog box may appear to not open on your screen. This can sometimes be caused by the dialog box opening off screen. i.e. you were previously using the software on a multiple monitor setup.
If nothing appears to be happening when you run a command, where you know a dialog box should open such as the Master Drawing Catalog or the Rebar shape manager, it may be because it is opening off screen.
The following article explains how you can recover a window that is opening off screen.
How to move an open window with the keyboard?
If you want to display the warning message that pops up before you confirm a particular action (such as expanding the work area to include new objects), after having previously chosen not to show these messages, please refer to the following article:
Show or hide "Do not show this message again"