The Event Viewer in Civil 3D is a pretty useful feature. It shows you “events” – if you create a data reference, it lets you know. If you have errors, or something wrong with your drawing, it lets you know. If certain events happen (crossing breaklines on a surface, for instance), it will let you know, and also let you zoom to that area where you’re having the problem. However, sometimes it seems like it shows TOO MUCH information.
For my purposes, I like to keep it turned off. The good news is that this is a drawing-specific setting. To access it, you go to the Settings tab of your Toolspace, right click on the drawing name, and select Edit Drawing Settings. In the dialog box that comes up, select Ambient Settings. In the property list below, expand the GENERAL tree. The third option down allows you to turn off the event viewer. Here’s an illustration: