Gers had allowed Carroll, 30, to travel to the Rams' training HQ after he had agreed to buy out the remainder of his contract at Ibrox.
Derby completed all the registration forms and even announced the signing on their club website. But they had to pull the plug as the Scots refused to release his documents. Rangers say Carroll will not be allowed to leave until they sign another keeper.
Rams boss Paul Jewell said: "I thought it was all done but now it is turning into a bit of a saga. It is annoying for me and for Roy. Rangers refuse to release his paperwork. It is all a bit embarrassing for both clubs.
"It is not ideal, especially as Roy is really keen to come and play here."