Deleting Junk messages from POP server

From MozillaZine Knowledge Base

Since moving from OE, the main thing I have missed is the automatic deletion of messages from the POP3 server when I have deleted them locally -- I either only keep the last week's messages or I have to delete messages by hand, to stay below the mailbox's size-limit.

The following solution has worked well, but expects you to have a server (e.g. Apache) with php available on your computer, as well as the extension php_imap.dll (on Windows; this can be found by searching the web; there is an .so version for Linux systems.) The extension has to be loaded of course, which requires the removal of one ";" (semicolon) in php.ini.

While this may be a rather specific solution, I hope it will inspire other people to write a more general one. Hopefully that option from OE will eventually find its way into Thunderbird.

The script

$server   = 'mail.your.server'; 
$username = 'username';
$password = 'password';
$junkfile = 'c:/path/to/folder/Junk';
echo "   Deleting messages marked as 'junk' from account $username on $server:\n\n";
$file = file_get_contents($junkfile);
$mbox = imap_open('{'.$server.':110/pop3}Inbox', $username, $password) OR 
     exit("   Error: unable to open online-Inbox.\n");
$numm = imap_num_msg($mbox);
echo "   There are $numm messages in the online-Inbox.\n\n";
$numj = preg_match_all("/X-UIDL/i", $file, $junk);
if ($numj == 0) {
  echo "   The folder $junkfile is empty.\n";
else {
  preg_match_all("/(?:Message-ID|Date): (.*)/i", $file, $junk);
$junk = join(' ', $junk[1]);
$done = 0;
for ($i = $numm; $i >= $numm-14; $i--) {
  $head = imap_fetchheader($mbox, $i);
  preg_match_all("/(?:Message-ID|Date): (.*)/i", $head, $rtrn);
  $rtrn = join(' ', $rtrn[1]);
  if (strpos(' '.$junk, $rtrn)) {
    if (preg_match("/From: (\".*\")/", $head, $from)) {
      imap_delete($mbox, $i);
      echo "   ... message deleted  From: $from[1] \n";
    elseif (preg_match("/From: (.{0,40})/", $head, $from)) {
      imap_delete($mbox, $i);
      echo "   ... message deleted  From: $from[1] \n";
    else {
      imap_delete($mbox, $i);
      echo "   ... message deleted:\n$head\n";
    if ($done == $numj) {
$date = date('D, d M y H:i');
if ($done == 0) {
  echo "\n   Done. No messages were deleted.\n   ($date)\n";
else {
  echo "\n   Done. $done message(s) was/were deleted.\n   ($date)\n";

How to use

To start,

  1. copy the above script into a file "deljunk.php" in a place where Apache can find it (-- note the one long line that should be read as one;)
  2. set the parameters in the first four lines of the php-section;
  3. set the Junk Mail Controls in Thunderbird to
    • "Move incoming messages determined to be junk mail to ..." and choose a folder, and
    • "When I manually mark messages as Junk: Move them to the "Junk" folder."

Then, whenever there are a number of messages in the Junk folder,

  1. move any messages that are not junk out of the Junk folder;
  2. compact the Junk folder (otherwise messages that have been moved out will also be deleted);
  3. while on-line, in your browser, run the "deljunk.php" script, like "localhost\path\to\deljunk.php": this will delete those of the 15 most recent messages on the server that are in the Junk folder;
  4. delete the mails from the Junk folder.

If the script regularly times out, it may be necessary to increase the number of seconds in the line "set_time_limit(30);"

(Needless to say, the script is provided as is, with no guarantees.)

Kai 17:10, 30 May 2005 (PDT)

One Alternative

Another lower-tech alternative to tricking Thunderbird into deleting Junk messages from a POP server is to use a Local Folders specific message filter. One of the actions available to message filters is "Delete from POP Server". Unfortunately, there's no "match all" conditional argument for filters, so I used "Status" "is" "Flagged", then flagged all messages in the Junk folder. After selecting the Junk local folder and choosing "Tools -> Run Filters on Folder", the next time I connect to the POP server(s), magically all of my junk mail is deleted.

ViperGeek 15:07, 14 Nov 2006 (EST)