To repair rotted door frame first remove rotted wood with a 5 in 1 or other sharp tool.
Repairing wood rot on exterior door frame.
Measure the damaged area make sure to remove any weatherstripping before cutting into the frame remove the rotted areas with a chisel saw knife or preferred tool confirm the measurements of the damaged area restore the missing areas of the door jamb by cutting your own replacement.
Then coat the rotted door frame area with wood hardener as shown.
Quickly learn how to repair a rotten door frame with miracle bond repair epoxy.
If your home has wood siding examine the siding around and beneath the windows for signs of swelling or discoloration.
Mix polyester wood filler or bondo wood filler and press it into the recess with a putty knife.