There is no Confirm control - normally, after you rearrange the accounts order in Account Settings, the new order is immediately visible in the main Folder list. One account will be designated as the Default account and will always appear first in the list, but the rest should be able to be rearranged.

The order of the accounts is stored in the file prefs.js (found in your profile folder), in the line "mail.accountmanager.accounts". This file should be automatically updated with you rearrange the accounts and should not be manually edited, especially when Thunderbird is running. Can you, when Thunderbird is shut down, locate this file and tell us if it's date and time coincides with the last time you ran it? There are other things to check, but that will tell us something significant.

Hi Lin, many thanks. The prefs.js file seems to update regularly - last time it was refreshed was 5 mins ago. However if I try to rearrange the accounts again right now, it doesn't seem to update... There are four more prefs#.js numbered 1-4, which are six years old. When I close Tb and re-open the prefs.js is refreshed, but the wrong order persists. Any thoughts much appreciated

I did some experimenting and I understand the process better but I still don't know why you're experiencing what you are.

The accounts order is stored in prefs.js . Normally, when you rearrange the accounts, that file is immediately updated by Thunderbird and is saved permanently when you exit the program. My first thought was that that file was somehow marked as read-only and not updatable, but the fact that your file changes date/time when you exit tells me that it's generally writable but for some reason, your new account order changes are not. What's mysterious about this is that your other various changes and preferences (presumably, since you don't mention them) *ARE* being saved, so why not those particular ones?

The only reason I know of would be that you also have a user.js file that has the mail.accountmanager.accounts line in it, which would take precedence over your manual re-ordering. It seems unlikely, but I have to ask: do you have a user.js file with a customized accounts order or any other directives that might influence that?

Otherwise, I'm out of ideas. Sorry.

Hi Lin, again many thanks for your help. I have no particular customized accounts order in the user.js file, at least not one that I consciously created. I don't change my prefs a lot, so if I do it may well be that these also go unrecognized in the prefs.js file. I suppose deleting any of these .js files to see them being regenerated is a bad idea, reading the documentation?

Goto Troubleshooting information on the help menu. Press Ctrl+F to open the find on this page Type legacy. Are there any legacy stylesheets?

just above that should be security software. What is that saying?

Scroll up to the addons heading. What is listed? (note you can highlight with your mouse and press CTRL +C to copy items highlighted and then paste into your reply on the forum. Ctrl+V)

Hi, many thanks for your help. Legacy stylesheets: Active: false / style sheet userContent.css

Security right above that: Microsoft Defender Antivirus

Addons: Bing extension bol.com extension DuckDuckGo extension FiltaQuilla extension Google extension LookOut (fix version) extension Marktplaats.nl extension Search Results Sort By Date Not Relevance extension Wikipedia (nl) extension Systeemthema – automatisch theme Donker theme Licht theme