Simon Weaver named the same starting XI and substitutes that collected all three points at Ebbsfleeet last weekend as they returned to The CNG Stadium following two away fixtures.
Despite the long journey North it was Dover who started the brightest, a free kick on the edge of the box followed by successive corners gave Town something to think about in the opening three minutes.
Dover continued to have the better of the chances in the opening exchanges, in the eleventh minute Town stopper James Belshaw was forced to make a good save after an Effiong effort from long range, before Dover captain Mitch Brundle curled and effort just wide of the post.
The first big chance for Town came in the 20th minute when, after a succession of corners, Joe Leesley's cross found Liam Kitching at the back post whose effort look certain to go in but was stopped on the line by an impressive reaction save by the Dover Athletic stopper.
Town's persistence would eventually pay off though, in the 26th minute the home side won a freekick on the edge of the box after Josh Falkingham was fouled, a late challenge from Bedsente Gomis.
Leesley stepped up to take the freekick, whipped a lovely cross to the back post where Callum Howe simply had to head across goal to find a sliding Aaron Williams to claim his fourth of the season and third in three games.
A few minutes later the game could've returned to level pegging, Anthony Jeffrey cleverly worked his way into space and managed to get a shot away, but Langmead was there to divert the effort behind for a corner.
After the Town goal, chances were limited for both sides. Leesley took aim from range but had his swerving shot parried away by Walker just moments before the half time whistle.
Dover Athletic had a dream start to the second half, in 46th minute a blinding run down the wing by Jeffrey, followed by a cross which picked out Inih Effiong who simply just turned and managed to slot the ball beyond Belshaw.
Moments later there was a Penalty shout for Town as a Leesley effort was deflected towards Williams and the Town forward was seemingly brought down in the box, but the referee saw no wrongdoing and Dover managed to clear their lines.
Dover looked like a team rejuvenated, Jeffrey continued to cause problems for the Town defence with his electric pace.
Despite the setback Harrogate still had a few chances to take the lead for the second time, both Langmead and Leesley saw their headed efforts cleared off the line and go over the bar respectively.
A great move by Dover saw them rattle the bar in the 62nd minute when Jamie Allen volleyed into the ground and then strike the bar.
Dover wouldn't rue there missed opportunity for long, as a great run into the box by Effiong evaded the Town defence and gave the tall striker an opportunity to scuff an effort into the bottom corner.
Now in the unfamiliar of being behind in a game Town still rallied to find an equaliser after two successive corners resulted in two headed efforts by Langmead narrowly missing the target.
Going into the final ten minutes the game seemed like it wasn't going to fall Town's way, George Thomson and Falkingham charged forward to try and rejuvenate Harrogate and possibly salvage a point, but both their efforts failed to test the Dover keeper.
Extra Time arrived, and Town were still pressuring the Dover goal, striking gold as Leesley picked out Langmead in the box who guided his header to back of the net, securing a point Town in the 4th minute of extra time.
A great game was then slightly over shadowed as Dover Player Jeffery received a red card in the closing stages of the game, completely losing head and clashing with Thomson before being sent to the changing rooms early.
Report by Isaac Martin
Town: Belshaw, Falkingham, Howe, Burrell, Thomson, Emmett, Leesley, Langmead, Williams (Thewlis 67'), Muldoon (Beck ‘61), Kitching
Subs not used: Cracknell, Agnew, Kerry
Goals: Williams 26, Langmead 90+4
Booked: Howe, Thomson
Dover Athletic: Walker, Passley, Lokko, Essam, Jeffrey, Brundle, Allen, Effiong (Massanka '84), Gomis (Nortey '71), Lewis, Debayo (Okosieme '80)
Subs Sho-Silva, Adebowale
Goals: Effiong 46, 66
Booked: Gomis, Brundle, Debayo
Sent Off: Jeffery
Referee: A Miller