Changing the Subject

Have you ever received an e-mail with a blank subject line? Of course you have; everyone has. If you are like me, you want a way to provide a meaningful subject line both to identify the contents of the message and to help search for that message in the future whenever the need arises. Unfortunately, users of Mozilla's Thunderbird e-mail client cannot directly edit the subject line with the base program alone.

There is a Thunderbird add-on called TB Header Tools Extension that apparently used to work well in older versions of Thunderbird. Regrettably, it is no longer maintained, having been last updated in July 2005. As a result, it no longer works with any recent version of Thunderbird. Other developers have revised the original extension, but those unofficial versions are not supported by Mozilla, and they reportedly work in some cases but not others. I therefore generally steer clear of those unreliable, unofficial add-ons.

In the course of Googling this topic, I stumbled upon one interesting suggestion that did seem to hold promise at first blush. The writer's suggestion was encouragingly simple: copy the message to the Draft folder, then edit the message to change the subject line, save the change, and move the message back to its original folder.

That method appeared to work: it did succeed in changing the subject line. However, it also changed the sender's name to that of the mailbox owner (namely, me) instead of the original/actual sender, and it also overwrote the original time and date with the time and date of the edited change. If I were to later search for messages from the original sender, the e-mail in question would no longer even appear. Thus, this method does more harm than good.

Even though that approach ultimately failed, it did set me to thinking. I already have a marvelous add-on called ImportExportTools that is fully supported by Mozilla and is actively maintained. As its name implies, it allows users to export and import individual messages to and from the .eml file format. The beauty of this solution is that users can edit .eml files with any basic text editor. With this add-on, it becomes a simple matter to export the message, open the saved message in a text editor, type the desired new subject line, save the newly edited file to the same .eml format, and import back into Thunderbird.

Eureka! The subject line of the imported message now reads as I intended, and the message still reflects the original sender and date/time stamp.

So now whenever anybody tells you "Don't change the subject!" you can blithely ignore them and change the subject to your heart's content.