This request cannot be completed becaus the link you followed or the form you submitted was only valid for minutes. (Unable to logout from webmail)

If you are facing the error while logout in horde then don’t worry this is a bug of horde. I am providing you steps to resolve it.

There is a math bug in the Horde.php checkRequestToken, the
paranthesis are missing

cd /var/www/html/horde-webmail-1.2.3/lib/VFS/

edit Horde.php

instead of


if ($_SESSION['horde_form_secrets'][$token] +
$GLOBALS['conf']['urls']['token_lifetime'] * 60 < time()) {
return PEAR::raiseError(sprintf(_("This request cannot be
completed because the link you followed or the form you submitted was
only valid for %s minutes"),
$GLOBALS['conf']['urls']['token_lifetime']));
}


it should be


if (($_SESSION['horde_form_secrets'][$token] +
$GLOBALS['conf']['urls']['token_lifetime']) * 60 < time()) {
return PEAR::raiseError(sprintf(_("This request cannot be
completed because the link you followed or the form you submitted was
only valid for %s minutes"),
$GLOBALS['conf']['urls']['token_lifetime']));
}

I Have tried it and it works.

Note: If you are using windows operation system then path of the horde.php file is
C:\Inetpub\vhosts\webmail\horde\lib