TB can't see messages in a folder -and/or attachments get lost

Question

I solved this awkwardly (but only for seeing the mail body- not for retrieving attachments)
, but it may help others.
i have messages in inbox with wdseml type.
i have re-indexed after deleting global-messages sqlite, and they still can't be found.
I also re-installed (31) and re-indexed today.
Originally i noticed the problem when i was searching and when i clicked on a message to view it the content was missing even though the subject was found.
Then i noticed that all messages from June 6 to Sept 15 had the problem for 1 inbox. All i can recall that might be relevant is that i may have compacted the db about then, or moved messages from one folder to another or both.
Following on another tip, i tried to repair the file under tools. Then all of those messages (550) in the date range disappeared from the search facility as well.
Ok, my solution.
Deep in Appdata for your user id under Roaming..Thunderbird..Profiles..Mail you will find your Inbox or whatever it is that TB can't see.
These in later releases have type *.wdseml;
On the top right of your TB there is a pull down one of which is Tools and therein you find Import/Export
(come to think of it, i think it is an add-in i found and installed some time back, sorry can't remember)
The tool offers you the ability to import files of type *.eml, but not *.wdseml
You have to copy those files to a new folder with a name like C:/recoverMail.
Then open a cmd.exe as administrator and rename *.wdseml to *.eml
then you can use the Import tool to get back visibility to your emails.
good luck

Answer 1

ok, I suggest you take an email message that contains attachments. Press Ctrl +U in thunderbird and you will see the message source. In a series os MIME documents in that text will be your attachments.
People almost universally assume they are sending files as attachments. The reality is a sleight of hand. EMail at it's inception was a text medium, and at it's heart it still is. That PDF file your attaching has to be converted to text before it can be a part of an email. This is called mime encoding and luckily is covered by an internet standard so most stuff is universal between mail clients. The result is your 500Kb file is converted to mime and in the process grows about 30-40% So when you ask questions like where are attachments stored, the answer is "in the body of the message"
The message view you get when you press Ctrl+U is not only the exact source of the message as transmitted over the internet it is an exact representation of the message if it was saved as an EML file.
Thunderbirds mbox files are simply a load of EML files stacked one after the other with a blank line at the end and a from line to start them. When Thunderbird is closed you can open them in a text editor and again see your mail in it's raw text representation.
So when you say the attachments were there, and then they were not, your saying that fundamentally the mime encoded text of a message has changed. Thunderbird does not go through some fancy editing process when you drag a message from one folder to another, it just copies a block of text to a new location, deletes it in the old location and pretends it moved something. If you said the message disappeared I would be all over it as a possible bug. Parts of it disappearing I simply don't understand as Thunderbird sees a message not some part of the message. Programs that go out of their way to see parts of a message even when stores as a mime encoded text file are anti virus programs, what programs are proud of the fact they insert themselves into every disk read and write. Again anti virus programs.
The following is a standard text used for diagnosing Thunderbird issues. Many challenge the validity, but using both Thunderbird's and the operating systems safe modes are the only ways to get rid of the all pervasive security software that is so often the cause of issues.
To diagnose problems with Thunderbird, try one of the following:
*Restart Thunderbird with add-ons disabled (Thunderbird Safe Mode). On the Help menu, click on "Restart with Add-ons Disabled". If Thunderbird works like normal, there is an Add-on or Theme interfering with normal operations. You will need to re-enable add-ons one at a time until you locate the offender.
*Restart the operating system in '''[http://en.wikipedia.org/wiki/Safe_mode safe mode with Networking]'''. This loads only the very basics needed to start your computer while enabling an Internet connection. Click on your operating system for instructions on how to start in safe mode: [http://windows.microsoft.com/en-us/windows-8/windows-startup-settings-including-safe-mode Windows 8], [http://windows.microsoft.com/en-us/windows/start-computer-safe-mode#start-computer-safe-mode=windows-7 Windows 7], [http://windows.microsoft.com/en-us/windows/start-computer-safe-mode#start-computer-safe-mode=windows-vista Windows Vista], [http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/boot_failsafe.mspx?mfr=true" Windows XP], [http://support.apple.com/kb/ht1564 OSX]
; If safe mode for the operating system fixes the issue, there's other software in your computer that's causing problems. Possibilities include but not limited to: AV scanning, virus/malware, background downloads such as program updates.