MS Access Query to update Trying to update Packet.MSGState to P where if not R or D and it is Y in table Packet.MSGState 

UPDATE Packet SET Packet.MSGState = 'P'
Where (MSGState &lt;&gt; 'R' and  MSGState &lt;&gt; 'D') and
Exists
(Select  MSGTO.Selected
From MSGTO
Where MSGTO.MSGTO = Packet.MSGTO and  MSGTO.Selected = 'Y')


Thanks Kevin
Use IN clause as following

UPDATE Packet SET Packet.MSGState = 'P'
Where (MSGState &lt;&gt; 'R' and  MSGState &lt;&gt; 'D') and
Packet.MSGTO IN
(Select  MSGTO.MSGTO
From MSGTO
Where  MSGTO.Selected = 'Y' and MSGTO.Selected IS NOT NULL )