The site, which has been offline since the end of March following a legal complaint by PR firm Hackford Jones, is back this morning but with all of the archived posts removed.
The apology reads: "The posting referred to two reported statements by Tulisa Contostavlos through her PR agents, Hackford Jones. The first statement was made in August 2011 stating Tulisa's belief that a reported 'sex tape' was a fake, and a second statement which she made on 22 March 2012 confirming that a 'sex tape' which had emerged was genuine.
"In the posting we wrongly stated that the first statement had been made only shortly before the second statement. We now accept that we dated the first statement inaccurately, and that it was actually made seven months earlier than was claimed in the posting.
"We also accept that the first statement was made when Tulisa had not seen any tape and that she did not believe that it was genuine, and that Hackford Jones repeated Tulisa's denial in good faith."
It continues: "Hackford Jones are concerned that this error implied that they had made the first statement with the aim of deliberately misleading the public. This was certainly not our intention.
"If any reader did in fact draw this impression from the posting we regret this and hope that this apology sets the record straight. We state categorically that we did not intend the posting to suggest that Hackford Jones had deliberately misled the public.
"We apologise to Hackford Jones if any readers thought we had suggested otherwise. We also apologise again to them for the inaccuracy in dating the statements."