I am getting the error "schema has changed..." when I attempt to start logging data with the OPC Data Logger.

"Schema has Changed..." errors can occur for 3 reasons.

1. A change in the database table definition has happened since configuring the mappings for the Data Storage component in OPC Data Logger.
2. A change in the data presentation has happened since configuring the mappings for the Data Storage component.
3. Multiple mappings exist to the same column name.  You can only map to each column name once.

The fix to all of these problems is to remap your database to the correct data logger attributes:

1. Open your "Presentation mode" (whether it is Detail or Table mode)
2. Verify the attributes (of the tag) that you want to log are in fact listed. Modify the list as needed.
3. Close the window and save any changes, if any changed were made.
4. Open the "Data Storage" properties window for the desired database connection.
5. Click on the "Item to Field Mappings" tab.
6. Define which database table/stored-procedure COLUMN maps to which data logger item attribute.
7. Click OK to save the changes and to close the window.
8. Retry data logging.