Process for manufacturing a metal strip having a metal coating for corrosion protection, comprising the steps consisting in: - passing the metal strip through a bath of molten metal comprising 0.2 to 8% by weight of aluminium, and magnesium in the following proportions: - from 0.1 to 8% by weight of magnesium for an aluminium content greater than or equal to 0.2% and less than 4% by weight or - a content greater than 5% and less than or equal to 8% by weight of magnesium for an aluminium content greater than or equal to 4% and less than or equal to 8% by weight, and comprising up to 0.3% by weight of addition elements, the balance being zinc and unavoidable impurities, then - wiping the coated metal strip by means of nozzles which spray a gas on each side of the strip, said gas having an oxidizing power lower than that of an atmosphere consisting of 4% by volume oxygen and 96% by volume nitrogen, then - passing the strip into a confinement zone which is delimited: • in the bottom part by the wiping line and the upper outer faces of said wiping nozzles, • in the top part by the upper part of two confinement boxes placed on each side of the strip, just above said nozzles, and having a height of at least 10 cm in relation to the wiping line, and • on the sides by the lateral parts of said confinement boxes, the atmosphere in said confinement zone having an oxidizing power lower than that of an atmosphere consisting of 4% by volume oxygen and 96% by volume nitrogen and higher than that of an atmosphere consisting of 0.15% by volume oxygen and 99.85% by volume nitrogen. - passing the metal strip through a bath of molten metal comprising 0.2 to 8% by weight of aluminium, and magnesium in the following proportions: - from 0.1 to 8% by weight of magnesium for an aluminium content greater than or equal to 0.2% and less than 4% by weight or - a content greater than 5% and less than or equal to 8% by weight of magnesium for an aluminium content greater than or equal to 4% and less than or equal to 8% by weight, and comprising up to 0.3% by weight of addition elements, the balance being zinc and unavoidable impurities, then - from 0.1 to 8% by weight of magnesium for an aluminium content greater than or equal to 0.2% and less than 4% by weight or - a content greater than 5% and less than or equal to 8% by weight of magnesium for an aluminium content greater than or equal to 4% and less than or equal to 8% by weight, - wiping the coated metal strip by means of nozzles which spray a gas on each side of the strip, said gas having an oxidizing power lower than that of an atmosphere consisting of 4% by volume oxygen and 96% by volume nitrogen, then - passing the strip into a confinement zone which is delimited: • in the bottom part by the wiping line and the upper outer faces of said wiping nozzles, • in the top part by the upper part of two confinement boxes placed on each side of the strip, just above said nozzles, and having a height of at least 10 cm in relation to the wiping line, and • on the sides by the lateral parts of said confinement boxes, the atmosphere in said confinement zone having an oxidizing power lower than that of an atmosphere consisting of 4% by volume oxygen and 96% by volume nitrogen and higher than that of an atmosphere consisting of 0.15% by volume oxygen and 99.85% by volume nitrogen. • in the bottom part by the wiping line and the upper outer faces of said wiping nozzles, • in the top part by the upper part of two confinement boxes placed on each side of the strip, just above said nozzles, and having a height of at least 10 cm in relation to the wiping line, and • on the sides by the lateral parts of said confinement boxes,