Image forming apparatus capable of performing recovery printing

An image forming apparatus that includes a sheet feeder configured to feed a sheet, and an image forming unit configured to form an image on the sheet fed from the sheet feeder based on an input job, and is capable of having an insertion unit connected thereto, for feeding one or more sheets placed on an inserter tray of the insertion unit by an operator, and inserting the one or more sheets placed thereon into sheets conveyed from the image forming unit, the image forming apparatus comprising:

• an inspection unit configured to inspect the image on the sheet conveyed from the image forming unit, and detect a defective sheet based on the inspection of the image;
• a control unit configured to interrupt the job in a case where a defective sheet is detected by the inspection unit, and change a discharge destination of the defective sheet and subsequent sheets which follow the defective sheet and are already printed;
• and
• an instruction unit configured to give an instruction for resuming the interrupted job,
• wherein the control unit is configured to, based on the instruction for resuming the interrupted job from the instruction unit, control the image forming unit to form an image which is to be formed on the defective sheet on a sheet newly fed from the sheet feeder, and control the insertion unit to insert the subsequent sheets which are placed on the inserter tray by the operator and fed from the inserter tray, on the newly fed sheet.