Updating to latest release of Thunderbird

The general answer is, Yes, install over the current version. But prepare in advance by checking a couple of things... - What is your operating system? - Is your current Thunderbird 46-bit or 32-bit? - Determine where your current version is from. That is, was in installed from an installer downloaded from the official source ( https://www.thunderbird.net/en-US/thunderbird/all/ )? Or was it installed from a "store", like Microsoft or Apple? If it was installed from thunderbird.net, download the latest release version from the link above, making sure you get the installer with the same "bitness" as your current. You can install right over the old version and your data should remain intact. Note that I said SHOULD. Just to be safe, as with all things computer, it's good practice to make a safety copy of your Profile, just in case something goes wrong. This article explains how: https://support.mozilla.org/en-US/kb/profiles-where-thunderbird-stores-user-data#w_backing-up-a-profile It's also good practice to make regular backups of your Profile if your email store is precious to you.