I had the same problem, but only in an mde where the database window was not
visible. Various suggestions concerning displaying the database window
' DoCmd.SelectObject acReport, "rzzUserStatus", True
before using SendObject and hiding it afterwards
' Application.RunCommand acCmdWindowHide
worked sporadically for a while, or generated errors of their own. Finally,
for totally unknown reasons, the error message went away after commenting
out both the above lines, leaving just the SendObject as it was originally.
Go figure.