This will recover the good messages and improve the correctness of the filter for the future. Note: You should frequently (daily or weekly) check your Junk folder for good messages wrongly marked as junk by Thunderbird and mark them as not junk.

Or you can press J on your keyboard to mark one or more selected messages as junk.

You can also click the Junk button on the message header toolbar:.

You can click on the little icon in the 'junk' column of the message list:.

There are several ways of marking messages as junk. So it is important to mark messages as junk before deleting them. In order for Thunderbird's junk filter to be effective, you must train it to recognize messages that you consider to be junk and messages that you consider to be not junk. Training the junk filter Tell Thunderbird what is JUNK ≡ > Account Settings > Your Account > Junk Settings Any messages from senders whose email address is in a whitelisted address book will not be marked as junk by Thunderbird.

In this section, you can also select address books which will be used as a whitelist. The junk settings in the account settings for each of your email accounts will override similar settings in the global junk preferences described above. ≡ > Preferences > Privacy & Security > Junk These settings will be used by all of your email accounts (although some settings can be overridden in the account settings, as shown below).

You can set global junk preferences to control what should happen to messages marked as junk. Junk filter settings Global junk preferences

3 Other ways of blocking unwanted messages.

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