All of your issues sound like anti virus activity to me. Try restarting the operating system in 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: Windows 8, Windows 7, Windows Vista, Windows XP, 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.

It's not... Something that runs on my system 24/7 just suddenly starts blowing up my email program?

Besides, trying safe mode was about # 8 on the list of troubleshooting ideas I tried BEFORE I posted here...  ;)

Yes something that runs 24/7 and updates daily, or more frequently, got a bad update. unbelievable I know. Or it could be McAfee and have had about 6 broken releases in a row.

So perhaps you could advise what you have done already. Before I suggest something else you have done. The quality of replies you get depends entirely on the quality of the information you supply.

Have you tried Thunderbird safe mode? (hold shift while it starts) Is your account IMAP or POP? What mail provider? Have you cleared out your temp folder in Windows? Does your anti virus scan the Thunderbird profile folders? what happens if you create an exception? What is the size of your profile on disk? Is there plenty of free space on the drive? Is the issue constant or intermittent? as your talking painting does the fix here help? https://support.mozilla.org/en-US/questions/1012145

Matt, I apologize if I came off as "snarky" in my last response... I'm on the tail-end of a 60-hour marathon trying to move 18 domains, websites, and their associated 200+ email accounts from one shared hosting provider to my dedicated server with another co-lo service. No excuse, but I am toast.

Let me go grab a wink and I will put on another more proper... (and complete) response...

THANK YOU for taking the time to try to help.  :)

• Safe Mode w/ networking = same result

• Thunderbird Safe Mode - same result

• Email Account is an IMAP account.

• Mail Provider? 1and1.com and AccuWeb Hosting... is that what you are asking?

• Windows Temp folder? Yes, I cleaned out my Windows Temp folder AND my AppData/Local/Temp folder.

• Both MalwareBytes and MS Security Essentials were working on the profile folder. Adding exception, reboot, delete a populated folder = Same Freeze

• My entire Thunderbird profile folder is 4.45 GB on the disk

Compacting Folders: Size on Disk: 4.45 GB (4,781,166,592 bytes) Size: 4.38 GB (4,712,943,150 bytes) Contains: 26,742 Files, 870 Folders

Just compacted every account, down from 5.28 GB.= Same Freezing (It's huge I know, but I am manually migrating email histories from a shared email server to a dedicated server and trying not to interrupt their service.)

• Space on Main System Drive (where profile is) = 292 GB FREE of 404 GB total. It's and EVO SSD. Issue is constant/consistent. EVERY time you delete or move a populated folder (1 or more saved emails), the view panel freezes on the last email viewed untill you change folders. Then the NEW folder headers panel lists the emails in the NEW folder correctly, BUT if you highlight or double-click a header, the view window goes blank (OR the new view tab, as the case may be).

• gfx.direct2d.disabled = true Set it to true... Same result... blank content panel.

Oh, and I just noticed that Emptying the Trash Can, while it works, does not update visually... Still looks like stuff in the trash, but clicking on anything to check brings up the error box saying "can't see that as it doesn't exist" error.

not an EVO850? http://www.extremetech.com/computing/199673-second-patch-for-ongoing-840-evo-ssd-performance-issues-being-prepped-by-samsung

Not an EVO 850... (typo?) It IS in fact the EVO 840 referenced in the article, but has been updated to the latest firmware.

I ran Magician, and the drive is slower than when it was first installed, but I'm not perceiving any slowdown on any other application.

I AM going to go do some registry cleaning and Pro de-fragging though... (SSD compatible of course).

just an experimental thing,

Try the beta here https://www.mozilla.org/en-US/thunderbird/channel/

I think I recall performance issues being addressed in it.

Also.

Does this one affect folders. Or does deletion of mail in the folder also cause an issue.

Could you log the IMAP activity https://wiki.mozilla.org/MailNews:Logging perhaps Thunderbird is firing off something to the server and it is taking an age to reply.

1) EarlyBird and Beta TBird - I'd like to try this, but I can't afford to risk breaking my profile with 15 IMAP accounts currently awaiting migration to their new homes. Thanks for the idea though... As soon as I put the migration to bed, I'll check it out.

2) ONLY folders... you can select any number of email headers and delete them, and you're OK... You can also (usually?) delete anEMPTY folder and be OK. BUT, if you DELETE or MOVE a folder from one location to another, ESPECIALLY if you were viewing an email in the folder you move before you to take action on the folder, the last email view flashes, freezes in view panel (sometimes a partial image), header panel empties (as expected). But then when you click into another folder, the email headers come up in the header panel, but when you select a header, the view panel remains blank.

Again, only "solution" is a restart.

I setup the logging batch file, closed TBird, ran the batch file, then opened TBird. Then I went into a folder and displayed an email... Then I moved that folder. Then I went to ONBOX and selected a header... no display.

Then I opened the log file and reviewed every line from the time I opened the folder I moved, until the end... I can follow the process, but I don't see an obvious error.

PS - I submitted a Bug Report 2 days ago on Bugzilla, but it doesn't look like a lot of work is being put in on new submissions.... lots of recent reports with no action or review at all.

what bug number?

You do know the small volunteer team is focused on the Thunderbird 38 release which was due last week I assume.

Let me look it up... Wow... that took some work...

Bug 1165535 - Email view window goes blank when you delete (et al.) a folder from the tree.

Should I put a comment with a link to this thread on the bug? Nevermind, if you think it should get the link, I'll let you do it. I don't have much experience working with Bugzilla or the team. I am NOT a coder/programmer at all...

I didn't know they were focused on a new release, but I figured something was up...

BTW, I am NOT dinging on the selfless folks who spend so much time on TBird AT ALL.... it's the best app out there IMHO, or I wouldn't be using it.

IF I was a programmer/coder, I'd be trying to help.  :)

Thanks so much for trying to help me on this!