Having trouble with Mozilla Thunderbird? A reader installed a Thunderbird update that caused all his messages to disappear, and change mail preferences. Here's how to recover from a Thunderbird disaster.

QUESTION My email is downloaded from Gmail to Mozilla Thunderbird, but a recent update appears to have deleted all my messages. Since then, Thunderbird has also ignored my preference for messages to be downloaded to their respective folders as soon as they appear in my Gmail inbox. Kimtrnc

HELPROOM ANSWER Unless Thunderbird has done something really horrible, all your emails should remain intact in your Gmail account. The most likely scenario is that these are still safe on your hard drive, too, but Thunderbird has lost track of them during the update and set up a new empty profile.

To verify that your Gmail messages remain intact, log into your Gmail account via your favoured web browser and look for them. If you can't immediately find your messages, look in the Bin folder. Anything placed here stays put for 30 days only, so time is of the essence.

If your messages are present in Gmail, back up your email, uninstall Thunderbird from your system and start afresh. You can then configure it to download messages from your Gmail account in the same way that you had it set up previously.

A simple way to back up your Thunderbird email is with MozBackup. This can back up your mail and contacts stored in Thunderbird, as well as data from other Mozilla applications, such as Firefox.

Alternatively, you can manually back up your Thunderbird profile by locating and copying to a safe place your profile folder.

The location of this folder will vary, depending on which version of Windows you are running. Look under Tools, Account Settings, then scroll down the left pane and click Local Folders. The Local Directory will be displayed in the right pane.

Browse to your profile folder in Windows Explorer. You may find two folders here if Thunderbird created a new profile following the update. Back up both folders to rule out any data loss. See tinyurl.com/cnqny for detailed instructions on backing up profiles.

You'll now be able to roll back your changes should anything go wrong when uninstalling and reinstalling Thunderbird.

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