Ubuntu 16.04下SpamAssassin未过滤得分超阈值垃圾邮件求助

Let's break down the issues and fixes step by step:

First, Clarify the Obvious from Your Provided Header #

The email header you shared shows X-Spam-Status: No, score=-5.0 required=3.0 — this mail is not spam (score is way below your 3.0 threshold), so it’s expected that it wouldn’t get moved to probably-spam. If you’re seeing other emails with scores above 3.0 that aren’t being filtered, focus on those for debugging.

Step 1: Verify Which Emails Actually Meet the Spam Threshold #

First, confirm which messages in your mbox have scores exceeding your required value. Run this command to extract all spam status headers:

formail -s grep 'X-Spam-Status' < mbox

This will list every email’s score and status. Note any entries where score=[number] is ≥3.0 but still marked as No — those are the ones you need to investigate further.

Step 2: Check Your Procmail Rule Order & Configuration #

Procmail processes rules top-to-bottom, so your SpamAssassin processing rule must come before your spam filtering rule. Here’s a correct example of what your procmail.rc should include:

# First, pass mail through SpamAssassin (spamc is the lightweight client)
:0fw: spamassassin.lock
* < 256000  # Skip large mails to save resources (adjust as needed)
| spamc

# Then, filter spam to probably-spam folder
:0:
* ^X-Spam-Status: Yes
probably-spam

If your filtering rule comes before the SpamAssassin rule, Procmail will check the (unprocessed) email headers before SpamAssassin adds the X-Spam-Status tag — so it’ll never match.

Step 3: Test SpamAssassin’s Functionality Directly #

Is SpamAssassin actually scoring emails correctly? Grab a copy of a problematic email (save it to a file like test-spam.txt) and run:

cat test-spam.txt | spamc -v

Look at the output’s X-Spam-Status line. If the score here doesn’t match what you expect, check your local.cf configuration:

grep 'required' /etc/spamassassin/local.cf

Ensure the required value is indeed set to 3.0. Also, update your SpamAssassin rules (critical for accurate scoring on Ubuntu 16.04):

sudo sa-update

Step 4: Enable Procmail Logging to Debug Execution #

Add these lines to the top of your procmail.rc to see exactly what’s happening during processing:

LOGFILE=$HOME/procmail.log
VERBOSE=yes

Re-run your original command (formail -s procmail ~/procmail.rc < mbox), then check procmail.log. Look for lines like:

• Match on "^X-Spam-Status: Yes" (confirms the rule triggered)
• Delivering to probably-spam (confirms the mail was moved)
  If you don’t see these, your rule isn’t matching — double-check the regex or rule order.

Step 5: Confirm Folder Permissions #

Make sure your probably-spam folder exists and has the right permissions for your user:

ls -ld ~/probably-spam

If it doesn’t exist, create it:

mkdir ~/probably-spam
chmod 700 ~/probably-spam

Procmail can’t move mail to a folder it can’t write to.

内容的提问来源于stack exchange，提问作者ComfortMoose