47. My app sometimes crashes when the user clicks on a tree control. Why?
This has happened to me if the user clicks on the
tree control while my code is programmatically updating it (typically removing
an item). The giveaway symptom is that the Dr Watson log contains lots of
references to COMCTL32 ordinal 234. It doesn't happen often, because the timing
has to be JUST right to produce the problem.
This is caused by a good old-fashioned bug in the
version of COMCTL32.DLL shipped up to and including IE4: But I can't get
Microsoft to admit it, despite being able to repro it with a tiny little test
program <sigh>. Installing IE5 fixes the problem, because this provides a
newer fixed version of the control DLL.
Fortunately, there is now a standalone update
utility to update your COMCTL32 without having to install IE5. Go here to get it:
http://www.microsoft.com/msdownload/ieplatform/ie/comctrlx86.asp
