When you work offline, AutoCAD Map 3D caches all your feature data connections.
This functionality is for geospatial features only. For information about working with shared drawing files, see Overview of Sharing Attached Drawings.
Clear the cache periodically to improve performance. To be sure that you are working with the most current data for a data source, rebuild its cache by refreshing its layer.
For more information, see Checking Out Features.
You can still check out and edit features while you are offline. When you return online, AutoCAD Map 3D attempts to lock features that you checked out while you were offline. Non-feature data cannot be checked out, so you cannot edit it unless you are connected to its source.
For more information, see Checking In Features.