The 20-year-old had agreed a move to join the Serie A strugglers before the window closed, but the Italian Football Association announced that they did not receive his papers in time.
The player's agent Mino Raiola said that this was down to a faulty Wi-Fi connection at the hotel he was staying at, and the club and player now face an anxious wait to see if they will be given the green light.
"It's ridiculous that the internet connection has not been working correctly," his agent Mino Raiola told Sky Italia.
"We completed all the documents before the deadline but we don't know if they arrived in time."
Kasami left Palermo for Fulham in 2011.