Dagenham completed the double to inflict on Notts two of their most embarrassing defeats of the season, following up their 6-1 victory in November by becoming the eleventh visitors to win at Meadow Lane this season.
Though Notts were under pressure early on, there was no hint of the horror show to follow and, indeed, the home side had fewer but better chances to break the deadlock.
First, Richard Butcher mistimed his shot and allowed David Button to make an easy save and then Miles Weston had an equally glorious opportunity, but tried unsuccessfully to square the ball to Delroy Facey when he should have taken a pot himself.
Notts were made to pay dearly for these failures when Dagenham snatched a 34th minute lead.
Peter Gain, always influential in midfield, picked out Sam Saunders who let fly with a curling shot from his left foot which flew into the right-hand corner of the net.
As Notts toiled to find an equaliser the Daggers punished them with a smart second goal a minute before half-time.
The Daggers were awarded a free-kick which Gain took quickly and flipped the ball to Matt Ritchie, who ran forward ten yards before thundering his shot past Kevin Pilkington who was left helpless once again.
Notts had even more chances in the second half as they turned up the heat.
John Thompson had a good effort blocked before Button blocked from Mike Edwards at six yards. Then it was Gavin Strachan's turn, but he headed rather tamely wide.
Two minutes from the end Notts' cup of woe overflowed as Dagenham struck for a third time. Danny Charge who had just come off the bench, knocked the ball into the path of Ritchie who drilled it inside Pilkington's right-hand upright.
It was County's fifth defeat in a row - proof if any were needed that their season has fallen apart.