If loading an unversioned feature class in ArcMap to attempt nonversioned editing, the following error message may display when editing:
"Could not edit any of the map's layers. No data sources in the map are registered as versioned or you lack privileges to modify data sources which are registered as versioned."
By default, ArcMap edit sessions are set to perform versioned edits. This means that only data registered as versioned can be edited.
To resolve the error, configure the current ArcMap session to perform nonversioned edits. Information on the steps for nonversioned editing can be found in the Related Information below.
Versioned tab setting required to enable nonversioned editing