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How to permanently set default Thunderbird mail folder?

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  • Last reply by Matt

a.clarke
a.clarke
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After much research, I found no satisfactory solution, so I fixed it myself as follows:

1) Open Thunderbird and click on desired mail folder.

2) Close TB.

3) Use Windows Explorer to navigate to where "session.json" file is located. Mine was, "C:\Users\Administrator\AppData\Roaming\Thunderbird\Profiles\7a4c8p7s.default", but yours will be different. You can locate it by right-clicking on the mail folder from inside TB, then click "Properties". Make sure TB is not running before proceeding to step #4.

4) Right-click on "session.json" file then click, "Properties". Check mark the "Read-only" attribute box then click the "OK" button.

After much research, I found no satisfactory solution, so I fixed it myself as follows: 1) Open Thunderbird and click on desired mail folder. 2) Close TB. 3) Use Windows Explorer to navigate to where "session.json" file is located. Mine was, "C:\Users\Administrator\AppData\Roaming\Thunderbird\Profiles\7a4c8p7s.default", but yours will be different. You can locate it by right-clicking on the mail folder from inside TB, then click "Properties". Make sure TB is not running before proceeding to step #4. 4) Right-click on "session.json" file then click, "Properties". Check mark the "Read-only" attribute box then click the "OK" button.

All Replies (1)

Matt
Matt
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yeah, fine as long as you never want to change any of the other settings the file contains, like the contacts pane, reading pane toolbar settings etc.

There is no way to set a default in Thunderbird, there is a way to lock the user interface preferences stored in the session.json file.

You methods will mess with settings for; folderPane, messagePane, firstTab, quickFilter and it's sub settings so basically to fix a small problem you are crippling the user interface.

Perhaps you might be a lot better served to create a script that modifies the relevant setting in the session json file and launches Thunderbird.

There's a script here that will modify a json file for chrome settings. perhaps you could modify it. https://stackoverflow.com/questions/44427052/how-to-modify-a-json-file-in-a-script