I have a small polygon that I need to buffer. I can create the buffer just fine, but I want to be able to copy it into an existing feature class. For some reason I cannot do this. I have tried starting an edit session, select the buffer and do a copy/paste and that seems to work until I stop editing, then it disappears. During the edit session, I can edit into the attribute table, but when I stop editing it goes away. I have also tried append, and the geoprocessing message says that it completed successfully, but it is not there. I have appended buffers of a point to this feature class, so I know it should work. Any ideas on fixing this would be appreciated.
And the coordinate systems are the same? Did you try to see if a record was added to the table or zoom to full extent to ensure that it was in fact, not there?