When starting a versioned edit session, the following error message is displayed:
"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."
The error may be caused by the following:
- Data not registered as versioned
- Improper object permissions
- Feature class is in Load-Only IO Mode
This ESRI Knowledge Base article http://support.esri.com/en/knowledgebase/techarticles/detail/38022 explains how to determine the cause of the error and resolve it.