IMCE has been working on this site just fine 'til recently.
Now it has been pointed out to me that when a user selects another folder in the "navigation" pane the 'throbber' comes up and stays there forever. Users thought that IMCE had 'crashed' but I've found that if you reload / refresh the page while the throbber is turning when the page reloads the browser has gone to the previously selected folder.
This is the same behavior for any action that causes a 'wait', IMCE appears to be stuck but upon a reload the action has in fact occurred.
I've tried this with both the current recommended 6.x release and with the 6.x-dev release both with the same results.
I've disabled and un-installed all IMCE support modules and tried again with the same results.
I've installed ThemeKey and set Garland as the theme for "*imce*", same results.
I am not running Google Analytics or Secure pages.
Drupal is up to date at 6.25.
No errors are being written to Watchdog.
And that exhausts my ability to work out what's going on.
Can anyone help?