The 29-year-old had been on loan at the League Two club since November.
Harley, who spent just six months at Swindon, enjoyed a four-year spell with Exeter between 2007 and 2011.
City continue their league campaign on Saturday with a trip to Mansfield Town.
Restore Data
| Team | P | W | D | L | F | A | GD | PTS | |
| 1 | Birmingham CityBirmingham | 26 | 18 | 6 | 2 | 44 | 18 | 26 | 60 |
| 2 | Wycombe WanderersWycombe | 28 | 17 | 7 | 4 | 54 | 29 | 25 | 58 |
| 3 | Wrexham | 28 | 15 | 7 | 6 | 41 | 24 | 17 | 52 |
| 4 | Huddersfield TownHuddersfield | 27 | 14 | 6 | 7 | 39 | 23 | 16 | 48 |
| 5 | Stockport CountyStockport | 28 | 13 | 8 | 7 | 43 | 28 | 15 | 47 |
| 6 | Leyton Orient | 27 | 13 | 5 | 9 | 40 | 24 | 16 | 44 |
| 7 | Bolton WanderersBolton | 28 | 13 | 5 | 10 | 43 | 42 | 1 | 44 |
| 8 | Charlton AthleticCharlton | 27 | 12 | 7 | 8 | 34 | 26 | 8 | 43 |
| 9 | Barnsley | 28 | 12 | 6 | 10 | 41 | 39 | 2 | 42 |
| 10 | Reading | 27 | 12 | 5 | 10 | 42 | 41 | 1 | 41 |
| 11 | Lincoln CityLincoln | 28 | 10 | 8 | 10 | 34 | 33 | 1 | 38 |
| 12 | Mansfield TownMansfield | 26 | 11 | 4 | 11 | 34 | 32 | 2 | 37 |
| 13 | Blackpool | 27 | 9 | 10 | 8 | 39 | 38 | 1 | 37 |
| 14 | Rotherham UnitedRotherham | 27 | 10 | 7 | 10 | 32 | 31 | 1 | 37 |
| 15 | Stevenage | 26 | 10 | 7 | 9 | 23 | 24 | -1 | 37 |
| 16 | Wigan AthleticWigan | 27 | 9 | 6 | 12 | 26 | 27 | -1 | 33 |
| 17 | Exeter CityExeter | 28 | 9 | 5 | 14 | 32 | 42 | -10 | 32 |
| 18 | Peterborough UnitedPeterborough | 28 | 8 | 6 | 14 | 44 | 52 | -8 | 30 |
| 19 | Bristol Rovers | 27 | 8 | 4 | 15 | 25 | 43 | -18 | 28 |
| 20 | Northampton TownNorthampton | 28 | 6 | 9 | 13 | 25 | 43 | -18 | 27 |
| 21 | Burton Albion | 28 | 5 | 9 | 14 | 30 | 44 | -14 | 24 |
| 22 | Crawley TownCrawley | 26 | 6 | 6 | 14 | 26 | 46 | -20 | 24 |
| 23 | Cambridge UnitedCambridge | 27 | 5 | 6 | 16 | 28 | 49 | -21 | 21 |
| 24 | Shrewsbury TownShrewsbury | 27 | 5 | 5 | 17 | 26 | 47 | -21 | 20 |
| > League One Full Table | |||||||||
