In what was an instantly forgettable first half, both teams rather cancelled each other out with neither able to find a way through the midfield traffic.
Yet it had all started so promisingly for Caley Thistle with Dougie Imrie, making his first start for Inverness, setting up Don Cowie, but his effort from a narrow angle drifted narrowly wide of Lukasz Zaluska's goal with only six minutes gone.
It took another 20 minutes, however, for either side to create a meaningful opportunity, United midfielder Prince Buaben firing his effort straight at Michael Fraser from close range.
Five minutes later and it was Caley Thistle's turn to pose a rare threat to the visitors goal, but Cowie's first-time shot from 20 yards only found the grateful arms of Zaluska.
Neither goalkeeper had been seriously tested, although Buaben did have Fraser at full stretch four minutes before the break after working space for himself on the edge of the area.
The second half did little to raise hopes of better fare, but that all changed when United took an unlikely lead on 68 minutes.
Noel Hunt, on as a half-time substitute for the ineffective Mark De Vries, drove the ball at goal from 12 yards and Buaben was fortunate to deflect the ball into the back of net from close range.
This prompted Caley Thistle manager Craig Brewster to introduce forward Graham Bayne for the disappointing Marius Niculae and he almost made an immediate impact with a volley that Zaluska had to look lively to save.
Now chasing the game, Inverness pushed forward and Roy McBain should have done better on 79 minutes when Cowie's inch-perfect pass picked out his run, but his weak effort rolled harmlessly into the goalkeeper's hands.
It looked increasingly likely that United were going to steal all three points, but six minutes from time sub Markus Paatelainen ensured the points were shared as he fired high into the roof of the net from six yards from McBain's cross.
Cowie did have a chance to win the game in the 89th minute following a poor clearance by Zaluska, only to see Garry Kenneth get back to clear his 35-yard lob off the line.