The Inbox should be used as an In-box for incoming mail and not be used as a general storage folder.

If you use a POP Inbox or a synchronise subscribed IMAP Inbox, then those emails are being stored in an mbox file called Inbox in your Profile mail account.

When you download those emails, they are written one after the other in the Inbox mbox file in the order they were downloaded. The emails are not stored as individual .eml files.

When you see a 'folder' in the 'Folder Pane', in reality it is a 'file'. So you are saying that you have a single mbox text 'file' containing 10.000 emails. 10.000 + emails in one document. Just opening that document would use a lot of memory let alone searching it as well. So performance will be effected. But more importantly, it is highly risky, if something happens to that file, you could lose everything.

If you do not compact on a regular basis, that single text file will also contain 'marked as deleted' emails which will be hidden from view unless you physically access that file in the Profile. So the Inbox may be even bigger than you think.

Please do some basic housework on your Inbox before you do any compacting. Create some new folders. eg: Bills, Online Orders, Family, Friends, Clients...etc Move emails into suitable folders for storage. When the Inbox is empty, right click on Inbox folder and select 'Compact'.

Normally, you do not have to empty the Inbox before compacting, but in your circumstance, it would be the best approach, as you do not know if there is any corruption in that file and to coin a phrase 'you have all your eggs in one basket'.

You could then further manage the folders to keep them smaller and more manageable by Archiving all the older mail. That includes the Sent folder which can also get large if not maintained. Set up 'Archive Options' to store by month and year and keep folder structure. See info:

• https://support.mozilla.org/en-US/kb/archived-messages

Please note there will be some menu differences: Where it says; Tools | Account Settings, Ubuntu / Linus OS use: ' Edit' > 'Account Settings'

Please read how to maintain a healthy Thunderbird:

• http://kb.mozillazine.org/Keep_it_working_-_Thunderbird

OK, I have emptied my inbox:

1. I've created one folder for every year until the inbox was empty
2. I've compacted the Inbox
3. Search runs now very quickly

But: i'm completely against sorting all emails into folders like Bills, Online Orders, Family, Friends, Clients...etc:

1. From my email experience in the last 16 years I have learned that I'm never looking for emails in specific folders, as the might belong to communication which could be stored in other folders - I would hardly find the right folder...
2. Therefore a search function is a handy tool
3. A quick solution to empty the inbox was to put all mails into folders named as years (2011,2012,2013,2014) - no big deal to put them into the folders

Maybe I was a little bit too optimistic...

As always it didnt' last for very long... unfortunately the same problem as described came up again.

I have 0 messages in Inbox, Inbox was compacted, search isn't working, loading indicator doesn't rotate, only option is to kill Thunderbird if somehow possible.

A little bit off topic but anyway... I just can't understand why software doesn't really work nowadays (2014). For sake of capitalism the wheel has been reinvented a hundred times. Stuffed with features, themes, addons an tons of possibilities the simplest tasks can't be completed anymore. This is not only with thunderbird but many others as well.

I can remember times where computer software was having only a few essential features and real-life tasks have been accomplished very efficient. It wasn't necessary to have an army of nerdy specialists and (sometimes destructive) updates and patches all the time. Despite beeing a computer enthusiast I really ask myself where this leads us to.

re: Search Are you using this search method:

Edit > Find > Search Messages Search for messages in: Select either the folder on the mail account OR mail account name

Select: 'Match all of the following' for one condition OR where two or more conditions must both be true. Select: 'Match any of the following' where two or more conditions have been set but any of them could be true. Which did you select ?

Set condition: What did you select here? Click on 'Search' button

Please tell me exactly the process and what you select to search.

Please clear the global search.

Help > Troubleshooting Information Clickon 'show Folder' button

Exit/close Thunderbird now - this is important

look for and delete this file: global-messages-db.sqlite

Restart Thunderbird.

No, I was using the search field in the toolbar.

As a former MS user, I thought of a similar functionality as the LookOut Plugin provided. Instant search without diving into dropdown menus.

Yes, your suggested method works very well as I just tried it.

:-)

Wow, Yes !!

This feature didnt' work for such a long time that I almost forgot how the screen was looking...

Thank you.

BTW. The file had 1.1 GB (...)

Good to hear all is now working as it should. One of the useful functions of using Edit > Find > Search Messages method, is that you can save the search in a folder, so that you can work through it more easily from the Folder Pane.

Indeed, this is a nice feature to search across folders and greatly improves ease of use.

Thanks for the hint.