I have a map that has a red exclamation (!) next to some of the layer, and the layer doesn’t draw. What is this and can I fix it?
The ArcMap MXD file cannot find the file in the directory specified. Several things can cause the data source path to be lost, but the most common are: 1) the file has been moved or renamed since the MXD file was last opened; 2) the user does not have access to the directory where the file is stored.
In order to restore a broken link, open the layer’s Properties, and select the Source tab. Click on the Set Data Source button. Navigate to the location of the file and click Add. This is also known as repairing a layer.