Posts Tagged ‘spam filter’

Emails erroneously flagged as spam

Wednesday, November 24th, 2021

Between yesterday Tue 23rd Nov 07:27 and tonight Wed 24th Nov 01:48 several hundred emails have erroneously been flagged as spam by our mail server. Please check your SpamBox folder for potential false positives during that period.

While we are constantly updating our filtering rules to catch the nasty spam, we are always doing our best to avoid flagging real emails as spam. We apologize for this and are still investigating the details of the root cause. Because the bulk of the messages were being correctly delivered, it took us several hours before we noticed the problem and could fix it.

Mail server maintenance on Wed, Jan 24

Friday, January 19th, 2018

Update 07:25 Migration finished, welcome on the new mail server!

We schedule a maintenance downtime for the D-PHYS mail server on

Wednesday, January 24, between 07:00 and 08:00 in the morning

During this period, sending and receiving new emails will have interruptions, thereby delaying incoming and outgoing mails. In particular, incoming external emails will not be lost, but held on the sender's side and will be delivered after the migration. Outgoing mail will be kept in your mail client until the connection is restored. The IMAP server will not be affected, so all email clients should have continuous access to the existing mailboxes.

This maintenance window will be used to migrate the first part of our mail server infrastructure to the latest version of the operating system and new hardware with fast SSD storage.

New location for SpamAssassin user preferences

We re-designed how our mail server is parsing the user's configuration for the spam filtering. Currently one has to edit the hidden text file ~/.spamassassin/user_prefs in the home folder. Starting from next Wednesday the spam filtering rules can be edited more conveniently through the settings in the Webmail interface. This will allow users to easily

  • accept mail from a given sender and never mark it as spam (whitelist)
  • reject mail from a given sender and always mark it as spam (blacklist)
  • set the threshold score required for any message to be considered as spam

The existing user preferences have been parsed and all of the above settings have been imported into the new setup. The contents of ~/.spamassassin/ will be ignored after the migration. Please contact us if you have questions regarding your advanced SpamAssassin rules.

Some incoming mails lost between Jan 9, 6pm and Jan 13, 11am

Tuesday, January 14th, 2014

On Monday morning we found out that large incoming mails (1 MBytes or larger) were dropped without leaving any error messages in our log files. These mails were lost between Thursday (Jan 9) evening 18:27 and Monday (Jan 13) morning 11:06. Some indicators (i.e. spam filter rules for this case) lead us to estimate the number of about 560 broken local deliveries to about 300 unique recipients.

If you expected e-mails with attachments close to 1 MB or larger within this time frame there is a high likelihood that they got lost. The only information we still have about these mails are sender, recipient and arrival date and time. If you were one of these recipients, please contact the sender to send it again.

You can check on this web page if mails you should have received were lost. You'll have to log in with your D-PHYS account and will see sender (or mailing list) of and time when the lost mail arrived. Additionally we'll inform all affected recipients individually, too.

The problem occured after one of the software updates on Thursday which brought stricter code checking, and is solved since Monday morning 11:06.

The issue was caused by a long standing and subtle programming error in the check which prevents bigger mails from being inspected closely by the main spam filter for performance reasons. It was only triggered upon local mail delivery, so mails sent from D-PHYS to outside D-PHYS were not affected. E-mails to D-PHYS mailing lists (or other mailing lists) with archive should be available in the according mailing list archives.

We're truly sorry for any inconvenience this may have caused and have already taken measures so that similar issues won't result in mail loss from now on.

Update: it happens to the best of us: Gmail for iOS bug might cause data loss