diff --git a/lisp/gnus/nnimap.el b/lisp/gnus/nnimap.el
index d797e893f5..7f2ebe279e 100644
--- a/lisp/gnus/nnimap.el
+++ b/lisp/gnus/nnimap.el
@@ -407,8 +407,15 @@ nnimap-keepalive
 		      (time-subtract
 		       now
 		       (nnimap-last-command-time nnimap-object))))
-            (ignore-errors              ;E.g. "buffer foo has no process".
-              (nnimap-send-command "NOOP"))))))))
+	    (condition-case err
+		(process-send-string "NOOP")
+	      (error
+	       (if (string-search "has no process" (cdr err))
+		   (let ((buf (current-buffer)))
+		     (setq nnimap-process-buffers
+			   (delq buf nnimap-process-buffers))
+		     (kill-buffer buf))
+		 (signal (car err) (cdr err)))))))))))
 
 (defun nnimap-open-connection (buffer)
   ;; Be backwards-compatible -- the earlier value of nnimap-stream was
@@ -1910,6 +1917,10 @@ nnimap-find-connection
 		     '(open run)))
 	  (get-buffer-process (cadr entry))
 	(setq nnimap-connection-alist (delq entry nnimap-connection-alist))
+	(setq nnimap-process-buffers
+	      (delq (cadr entry) nnimap-process-buffers))
+	(when (buffer-live-p (cadr entry))
+	  (kill-buffer (cadr entry)))
 	nil))))
 
 ;; Leave room for `open-network-stream' to issue a couple of IMAP