Franz Kafka is reported to have told his close friend Max Brod that, if there was to be an ending to The Castle, it would probably involve K. being permitted to remain in the village until his death, but without official sanctioning of his status.  Kafka is also supposed to have told Brod that the story might simply never be completed and, as Kafka was dying of tuberculosis, he may very well have disposed of the notion of devising an ending to The Castle.  As with novels depicting dystopian or totalitarian societies characterized by massive all-powerful bureaucracies, be they the stories of George Orwell, Ray Bradbury, or any other author, Kafka’s fictional society defies easy comprehension.  When contemplating an ending to a story of such Orwellian or Kafkasque magnitude, one does enjoy the luxury of “thinking outside the box.”  In Chapter 7 of The Castle, Kafka includes an exchange between “the teacher” and K. that is nothing short of bewildering in its surrealism.  The teacher has come to reprimand K. for his “uncivil” behavior towards the village mayor:

“’I didn’t know I had been uncivil,’ said K., drying himself.  ‘But it’s true that I had something other than elegant manners to think about, something of importance to my very existence, which is threatened by a disgraceful official organization the details of which I need not describe to you, since you yourself work actively for the authorities.  Has the village mayor complained of me?’ ‘In what quarter would he have complained?’ said the teacher.  ‘Even if he knew where to turn, would he ever complain?  I have simply drawn up, at his dictation, as small memorandum about your conversation, from which I learned quite enough about the mayor’s kindness and the way you answered him back.’  As K. was looking for his comb, which Frieda must have tidied away somewhere, he said: ‘What? A memorandum?  Drawn up after the event, and in my absence, by someone who wasn’t present during the conversation?  Not bad, I must say.  And why a memorandum?  Was it something official?’ ‘No,’ said the teacher, ‘semi-official, and the memorandum itself is only semi-official. . .At least it’s down on paper now, and it does you no credit.’”

This is a very long quote for an eNotes answer, but it will be the only one used.  It depicts the kind of society for which Kafka’s writings were famous: nameless, faceless bureaucrats serving at the pleasure of an omniscient government that has no compunction about walking over its citizens.  When contemplating an ending, then, one can easily and rationally dispense with the suggested ending a dying Kafka conveyed to his friend, Max Brod.  A suggested ending, therefore, could involve K.’s being left in an unresolved state of limbo – which kind of occurs anyway – but without the luxury of being afforded the opportunity to live out his years in the village.  A more appropriate ending could very well include K.’s being held in confinement or simply denied entry by no identifiable authority representing no easily delineated government.  There is little in The Castle to suggest that K. would prevail in his efforts, and more to imply that he will fail, and fail miserably.  Send him on his way; dispatch him to a new form of purgatory where little to nothing makes any sense whatsoever.  Anyway, that’s what I would do.