Problem: The Start Editing option is disabled for a table
When attempting to edit a table, the Start Editing menu option is grayed out.
You can not edit delimited text tables, SQL tables, tables with read only file permissions, attribute tables belonging to 3D shapefiles, or attribute tables belonging to shapefiles converted from CAD drawings that contain blocked entities.
Solution or Workaround
If the table is a delimited text table, or a SQL table, export the table as a DBF file and add it to ArcView.
A. Open the table. B. Select Export from the File menu. C. Select the desired Export format (dBASE, INFO, or Delimited Text). D. Name and save the new table. E. Click OK.
A DBF generated from a SQL table will not be linked to the original database. To maintain a dynamic link, make changes to the table in the RDBMS application and refresh the SQL table in ArcView.
A 3D shapefile will indicate Z or M values in the Shape field of the attribute table. For example, PolylineM or PolylineZ.
If the above doesn't solve this problem, use Windows Explorer to check and change the file's permissions.
A. Start Windows Explorer. B. Navigate to the shapefile C. Select the files associated with the shapefile (SHP, DBF, SHX, PRJ, SBN, SBX). D. Right-click and select Properties. E. Uncheck the Read-Only option. F. Click Apply and OK.