[Orgmode] Entering effor estimates in column view of agenda view gives wrong-type-argument stringp, nil

[Charles Cave]

I recently installed 6.17c org-mode on Windows XP withg GNU Emacs.

When I create an agenda view, switch on column view, then
attempt to modify the effort estimate with shift-right arror
keys I get an error message Wrong type argument stringp, null.

I know this was working the other day but I think it was an earlier version
of org-mode.

This is the configuration of my file:

#+STARTUP: overview
#+STARTUP: hidestars
#+STARTUP: logdone
#+PROPERTY: Effort_ALL  0:10 0:20 0:30 1:00 2:00 4:00 6:00 8:00
#+COLUMNS: %40ITEM(Details) %TAGS(Context) %9TODO(To Do) %5Time{:} 
%6CLOCKSUM{Total}
#+PROPERTY: Effort_ALL 0 0:10 0:20 0:30 1:00 2:q00 3:00 4:00 8:00
#+TAGS: { OFFICE(o) HOME(h) } COMPUTER(c) PROJECT(p) READING(r)
#+TAGS: DVD(d) WAITING(w)
#+SEQ_TODO: TODO(t) STARTED(s) WAITING(w) APPT(a) | DONE(d) CANCELLED(c) 
DEFERRED(f)


And here is the stack trace:

Debugger entered--Lisp error: (wrong-type-argument stringp nil)
 
string-match("^[[<]\\(\\([0-9]\\{4\\}\\)-\\([0-9]\\{2\\}\\)-\\([0-9]\\{2\\}\\) 
+\\([^]-+0-9>
\n ]*\\)\\( 
\\([0-9]\\{2\\}\\):\\([0-9]\\{2\\}\\)\\)?\\)[^]>\n]\\{0,16\\}[]>]$" nil)
 (if (string-match (concat "^" org-ts-regexp3 "$") s) (progn (let* ... 
... ... ... ... ... ... ... ... ...)))
 (when (string-match (concat "^" org-ts-regexp3 "$") s) (let* (... ... 
... time-before time-after) (unless active ...) (setf ... ...) (setf ... 
...) (setf ... ...) (setq time-before ...) (setq time-after ...) (setf 
... ...) (setf ... ...) (mapcar ... ...)))
 org-colview-construct-allowed-dates(nil)
 (or (org-property-get-allowed-values pom key) (and (memq ... ...) 
(quote ...)) (org-colview-construct-allowed-dates value))
 (let* ((col ...) (key ...) (value ...) (bol ...) (eol ...) (pom ...) 
(line-overlays ...) (allowed ...) nval) (when (integerp nth) (setq nth 
...) (if ... ...)) (when (equal key "ITEM") (error "Cannot edit item 
headline from here")) (unless (or allowed ...) (error "Allowed values 
for this property have not been defined")) (if (member key ...) (setq 
nval ...) (if previous ...) (cond ... ... ...)) (cond (... ... ...) (t 
... ... ...)))
 org-columns-next-allowed-value()
 call-interactively(org-columns-next-allowed-value)