The editor doesn't respond after accepting the manuscript The journal editor accepted my paper and told me to ask his assistant about the next steps in the publication process. Four months ago I corrected some minor points and sent an updated manuscript to the assistant. Since then the editor's assistant remained silent. About two weeks ago I asked him about the status of the manuscript and next steps, but he hasn't replied yet. What should I do? Could the editor reject my manuscript after acceptance?
You should write to the editor and tell him what you have told us.  Really your concrete problem is that your correspondence has not been returned so you don't know what's going on.  Maybe everything is proceeding as it should, maybe it isn't, but you need a reply.  


  Could editor reject my manuscript after acceptance?


Why do you even ask?  Are you worried that the editor thought, "No, hang on, I don't want to publish this paper after all.  Let's not publish it, never contact the author again, and hope for the best"?!?  That's just totally loopy, unprofessional behavior.  In this big, bad world of ours, anything could happen, but the chance of this happening to you -- provided only that you are dealing with a partway reputable, professional journal (essentially: not a journal that you learned about via a spammy, semi-literate email) -- is negligibly small.

Just get back in contact with the editor ASAP and take it from there.  Be polite, but be persistent.  Give the editor a week or two to reply.  I honestly expect that he will.  If not, write to the editor-in-chief / managing editor / some other members of the editorial board.  You'll hear back from someone.  Again, don't assume that something has gone terribly wrong, and certainly don't worry that your polite, professional behavior will jeopardize the future of your paper.