A number of morning rush hour trains were affected by a signalling fault at Markinch on Tuesday.
The rail company confirmed the issue on social media at 6.30am.
Some train services between Edinburgh and Aberdeen were delayed or revised as a result, as well as services via Perth.
The fault was resolved at around 7:30am with services able to recommence.
ScotRail confirmed that employees were on site at Markinch working to fix the signalling fault.
Travellers can check if a planned journey is possible on the National Rail enquiries real-time journey planner.
The company arranged for rail tickets to be accepted on local bus routes at no extra cost until 8:30am.
Bus stop and timetable information can be found here.
ℹ️ UPDATE: Ticket Acceptance is now in place with @StagecoachEScot on the services below. Just show your valid rail ticket or Smartcard to the driver when you board the bus.
— ScotRail (@ScotRail) October 5, 2021