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Rohkem teavet

Prevent Thunderbird from modifying date of EML files

  • 4 vastust
  • 1 on selline probleem
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  • Viimati vastas gwaedin

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I archive important emails by saving them as EML files in relevant folders. Unfortunately, once in a while Thunderbird messes up my archives by redating all EML files in a given folder. That is, all EML files will be seen in Windows Explorer as having been modified today. Obviously if I open the email the date is correct but losing the date info on the file is quite annoying. Is there a way to prevent Thunderbird from doing this? It happens on different PCs, using different OS (Windows 7 and 10).

I archive important emails by saving them as EML files in relevant folders. Unfortunately, once in a while Thunderbird messes up my archives by redating all EML files in a given folder. That is, all EML files will be seen in Windows Explorer as having been modified today. Obviously if I open the email the date is correct but losing the date info on the file is quite annoying. Is there a way to prevent Thunderbird from doing this? It happens on different PCs, using different OS (Windows 7 and 10).

All Replies (4)

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re :That is, all EML files will be seen in Windows Explorer as having been modified today.

Thunderbird has nothing to do with the issue you mention.

When you choose to archive/save an email as an EML file in a folder (not in thunderbird) on your computer, that is the first instance of the file being created and therefore your Operating System will apply a date of creation of that file and when you access that file on another day, the computer will modify the date.

This is how all folders and files on your computer work. You are viewing the file contents using the Thunderbird program, but it is not Thunderbird which updates a file which is created and stored on your computer.

If you need to keep an easy to see record of the original date as seen when you open that email: You can either manually alter the filename to include the date, but this is a bit labourious, so I would suggest you use an addon extension called ImportExportTools to facilate this when creating the EML file.

How to install:

Once you have installed the addon extension, in 'Addon Manager' tab

  • click on the 'Options' box for ImportExportTools.
  • select the 'Filenames' tab
  • select 'Use the following format'

then you can choose what you would like:

  • eg: Subject, Name (sender) and Date
  • click on OK

see image as guide

now when you export email as eml file, it will append the date to the filename. Much easier to see.

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Thanks for answering! Hmm... I understand that the EML file date is the file creation one, and not the email date. That's fine. The point is that every month or so this date gets changed and all of the files in some folders are "updated". I assumed it was a Thunderbird issue but you definitely exclude it... what could it be then? Windows itself?

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Windows OS will update any file that is opened to show new 'modified' date.

There is a difference between the 'Date' header which is part of the contents of the file ( which Thunderbird can display) and the EML file creation and file modified date.

Hence why I suggest the addon. I use that addon so it can put the Date in the actual filename, this does not change unless you actually manually change it. It also means you can instantly see the date without even opening the file.

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"Windows OS will update any file that is opened to show new 'modified' date."

This is not true. Actually as long as I don't modify the file, the date stays there - usually. Therefore, I can order files by date in Windows Explorer and EML files appear "when" they belong to. However, once in a while, for reasons not clear to me, something changes the last modified date of all EML files in a folder (and only EML ones) to the current one.

I could try your solution but I'd be more happy if I could find out what is acting on the EML files date and stop it. I assumed it was Thunderbird simply because this only occurs for EML files.