Visual Basic - porque me sale este eroor?

Key column information is insufficient or incorrect. Too many rows where afected by update.

El codigo es el sig:

Set cn = New ADODB.Connection
cn.CursorLocation = adUseClient
cn.Open "PROVIDER=SQLOLEDB;Data Source=" & nameServer & ";User ID=sa;initial catalog=" & nameInit & ";"

Set adoCloneSabaRS = New ADODB.Recordset

cSql = "SELECT * FROMOM Yza_NoSaba "

adoCloneSabaRS.Open cSql, cn, adOpenDynamic, adLockOptimistic

adoCloneSabaRS.MoveFirst
Do While Not adoCloneSabaRS.EOF
adoCloneSabaRS!Revisado = "N"
adoCloneSabaRS.Update
adoCloneSabaRS.MoveNext
Loop