He has already been on loan to Conference club Halifax Town, and Accrington Stanley have also made enquiries about a loan deal.
Iron manager Brian Laws told the Scunthorpe Telegraph: "It is a crucial stage of the season at the moment and there is no way anyone is going anywhere."
McCombe's agent Craig Allardyce, son of Bolton manager Sam, has insisted McCombe's future lies with Lincoln City.
He claims to have a written assurance from Iron Chief Executive Don Rowing that the tall defender is available on a free transfer.
Terms have been agreed with Lincoln and it appears that McCombe's future lies down the A15, it is just a question of when he makes the move.
Imps assistant manager Gary Simpson said: "He fitted into our financial structure and terms were agreed with the lad, now it seems Scunthorpe are trying to stop it happening."