Ban on shoeing animals for man.
Neil Jackson is not able to carry out farriery for 28 days because of the ruling by the disciplinary committee of the Farriers Registration Council.
The committee found Jackson guilty of allowing Jonathan Lavelle to clench up and file nails to the front feet of a horse at Wolviston Rising School and Livery Yard, in Durham Road, Wolviston, near Billingham.
Mr Lavelle was not a registered farrier or registered apprentice farrier at the time of the incident in April 2011.
The committee said Jackson, from Bishop Auckland, was guilty of "serious misconduct in a professional respect".
The chairman of the committee said: "This goes to the heart of the Farriers Registration Act and is directly in contravention of the guiding principles in the Code of Conduct, namely to uphold the good reputation of farriers and to understand and comply with your legal obligations."
In November last year Jonathan Lavelle, of North Lane, Elwick, Hartlepool was given a six-month conditional discharge and ordered to pay pounds 300 costs by Teesside magistrates after admitting carrying out illegal farriery.
Mr Jackson's suspension will run from August 2 to August 29.