I've also just been bitten by this bug, as I was doing my weekly review. I'll try to see if I can write an ECM, but for the record this is what I was doing: I was in an agenda view sorted by the value of a LAST_REVIEW property, and I was repeatedly calling this function on the entries of the view: #+begin_src emacs-lisp (defun org-review-insert-last-review (&optional prompt) "Insert the current date as last review. If prefix argument: prompt the user for the date. If `org-review-sets-next-date' is set to `t', also insert a next review date." (interactive "P") (let ((ts (if prompt (concat "<" (org-read-date) ">") (format-time-string (car org-time-stamp-formats))))) (org-review-insert-date org-review-last-property-name org-review-last-timestamp-format ts) (when org-review-sets-next-date (org-review-insert-date org-review-next-property-name org-review-next-timestamp-format (format-time-string (car org-time-stamp-formats) (org-review-last-planned ts (or (org-review-review-delay-prop (if (equal (buffer-name) org-agenda-buffer-name) (or (org-get-at-bol 'org-marker) (org-agenda-error)) (point))) org-review-delay))))))) #+end_src the `org-review-insert-date` is defined as follows #+begin_src emacs-lisp (defun org-review-insert-date (propname fmt date) "Insert the DATE under property PROPNAME, in the format specified by FMT." (org-entry-put (if (equal (buffer-name) org-agenda-buffer-name) (or (org-get-at-bol 'org-marker) (org-agenda-error)) (point)) propname (cond ((eq fmt 'inactive) (concat "[" (substring date 1 -1) "]")) ((eq fmt 'active) date) (t (substring date 1 -1))))) #+end_src I could get out of the loop using "ctrl-G" but any further interaction with the todo buffer (expanding the task to see its properties, or changing the todo state) would result in further lockup. Restarting emacs let me do a few more entries (about a dozen) before it locked up again. Alan -- OpenPGP Key ID : 040D0A3B4ED2E5C7