000780 : Checking in data is not supported on this geodatabase release.
Description
Checking in data from a checkout is not supported in the release of the geodatabase you are connected to. This type of replication functionality is supported at ArcGIS 8.3 and beyond. If you receive this error, it means that a geodatabase you are connected to is from an earlier version.
Solution
You must use geodatabases with a minimum release version of 8.3.
11/18/2010