PROBLEM
The Table Options in ArcMap include the options to add or delete fields from a table. In some instances, these options are unavailable.
Note: The Add Field and Delete Field options are only available when user has the write access to the data and the data in ArcMap and ArcCatalog is not accessed by other users or applications.
Depending on the cause, use one of the following solutions:
Stop the edit session
Note: If the Editor toolbar is disabled, refer to ArcMap: Adding the Editor toolbar to enable it.
To resolve this issue, stop the edit session in the map document. Click the Editor button in the Editor toolbar, and select Stop Editing. The Add Field and Delete Field options are now available and can be used to add or delete fields.
Corrupted MXD file
In the event of a corrupted MXD file, open a new map document and add the layer to the map. The Add Field and Delete Field options are now available.
Get help from ArcGIS experts
Download the Esri Support App