Spanish giants Barcelona will not be able to sign any players until Janyary 2016, once the current transfer window closes after their FIFA appeal was rejected.
The Spaniards were given the 14-month ban after being found to have breached rules on signing international players under the age of 18.
However the ban was suspended until the hearing of their appeal, which has allowed them to spend over £120m this summer on new players, including Liverpool's Luis Suarez.
The club's only course of action will be to take the case to the Court of Arbitration for Sport (Cas), incidentally where Suarez last week had his four month footballing ban amended so that he could train with his team.
The ban will start in the next transfer window, early next year, which means their summer acquisitions will be unaffected.
And the Catalan club could, if they wanted, sign more players before the current transfer window ends on 31 August.
In a statement, the club said it would "continue defending its interests before the highest sporting authority, in this case the Court of Arbitration for Sport".
Barcelona added that the punishment was an "affront to the spirit" of their "world renowned" academy La Masia, which is regarded as being the foundation of the club's success in recent years. The academy has produced players such as, Xavi and Lionel Messi who have been vital to the team's dominance in recent years.
The Catalans will also have to pay a fine of 450,000 Swiss Francs (£305,000) and in a brief statement by FIFA, they said "FC Barcelona is to serve a transfer ban which will see the club prevented from registering any players at both national and international level for two complete and consecutive transfer periods."
The Spanish Football Federation (RFEF) has been told to pay a fine of 500,000 Swiss Francs (£340,000) and told to "regularise its regulatory framework and existing system concerning the international transfer of minors in football" within a year.