Is it also slow with Help > Troubleshoot Mode? Is it slow on *every* startup? How many accounts do you have? Any RSS?

Hi Wayne, thanks very much for replying. TB is slow on every startup. In Troubleshoot mode, TB starts very quickly, around 4 seconds. I see that this mode disables add-ons, which I do not have any of, but I permanently reset any addons. I also permanently reset menus and controls. Then TB started in about 4 seconds which is great. But TB then starts with View > Folders > All folders. When I switched this to View > Folders > Unified folders, TB kinda freezes for about a minute, and upon reboot, again takes a long time (30 seconds about) to start up. So the issue seems to be around using Unified folders..... I have 4 email accounts and no RSS. Any further help is much appreciated. (With being able to use Unified folders but have TB start quickly) Thanks again.

PS I also just noticed that one of my other issues: "Issues with forwarded messages" https://support.mozilla.org/en-US/questions/1428381 Seems to be fixed if I use: View > Folders > All folders. And not View > Folders > Unified folders. IE it seems this issue is also caused by using Unified folders.

PPS: Another issue I have: Inbox displays incorrect number of messages https://support.mozilla.org/en-US/questions/1428377 May also be caused by using Unified folders, because eg Unified folders inbox would be involved in summing the number of messages in the inboxes of individual email accounts. I say "may" because this is an intermittent problem and so I cannot replicate it all the time by switching between All folders view and Unified folders view.

I did the following: - Backed up my profile - Uninstalled TB and did a fresh install of TB 115.4.1 - Created new profile - Added from scratch my email accounts using Add Email Account - Copied my Local Folders over from old profile - Exported calendar and address books from old profile to new one

And this fixed this issue.

Thanks for that info, and marking the issue solved.

It sounds then like the problem was either Unified Folders, or a specific bad folder. In the future ...

Bad folder would be fixed by right+click on folder > properties > repair.

Unified might be fixed by

• Install https://addons.thunderbird.net/en-US/thunderbird/addon/unified-folders-debugging/
• If you do not see the "Unified Folders" heading in the folder pane, then click on "..." next to "New messages", click "Folder Modes", enable an additional folder mode to force the "Unified Folders" heading to appear
• in the folder pane, next to the "Unified Folders" heading, click on ⋮ three vertical dots, do not do "Reset Unified Folders"
• click Debugging Info > click Copy to Clipboard and save the clipboard somewhere
• click Close.
• in the Unified Folders heading click on ⋮ three vertical dots, and do "Reset Unified Folders". (DO THIS LAST)

Hi, sorry for my late reply.

1) Re fixing a bad folder, I have many folders, and I would not be sure which one I should repair.

2) I would install Unified Folders Debugging 115.3 addon but I noticed it gives a warning before install that says it will have access to my whole computer, and my company's security policy will not allow installing based on this warning.

3) I have solved this particular issue with Unified folders (TB takes a long time to start up) but I have other issues with Unified folders to the point I wont use Unified folders.

I am now considering trying to revert to an older version of TB