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My thunderbird whites out & "Not Responding" shows up? all to often. Can you help. Great other wise :-)

  • 7 replies
  • 3 have this problem
  • 7 views
  • Last reply by Toad-Hall

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It seems to happen when I really need to get in to an e-mail.. Murphys law :-)

TB locks up, says "Not responding" across the top , Then finally whites out. The rest of the computer is working fine, So I usually go do something else, & when I come back to TB its working again.

Thank you . I see you are supporting TB again with dedicated people , Awesome.

The Search feature is very helpful in Thunderbird. Thank you :-)

It seems to happen when I really need to get in to an e-mail.. Murphys law :-) TB locks up, says "Not responding" across the top , Then finally whites out. The rest of the computer is working fine, So I usually go do something else, & when I come back to TB its working again. Thank you . I see you are supporting TB again with dedicated people , Awesome. The Search feature is very helpful in Thunderbird. Thank you :-)

All Replies (7)

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Is this a Pop or IMAP mail account? What anti-virus software are you using? Do you scan incoming mail?


First I would access the anti-virus software and disable the scanning of emails.

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Thank you so much. But I do not know?

How does one know the difference between the 2 , (pop / imap) It is a Verizon account.

Also, I just use windows defender, I do not know how to scan incoming e-mail. I thought Thunderbird did that automatically?

Sorry , I am not very techy

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Re; Pop and IMAP Pop mail accounts can only access the server Inbox and download messages to your Thunderbird mail account Inbox.

IMAP mail accounts see a remote view of the server folders. You subscribe to see folders. Email headers are downloaded and when you select to view an email in the list, the email is retrieved from the server and downloaded to a temporary cache.

You can check which type by looking here: 'Tools' > 'Account Settings' > 'Server server Settings' for the mail account or Right click on mail account name in Folder Pane and select 'Settings' Then choose the 'Server Settings' for the mail account.

At the top on the right side, it will say 'Server Type'. What does it say ?


re: Defender: - on Windows Vista and 7 (see later posts for 8 and 8.1) Windows Defender is not a antivirus program, it is anti-maleware/antispyware, please do not think you are protected when only running Defender. There are some free anti-virus software or you can purchase one. An example :

re: I thought Thunderbird did that automatically Thunderbird is an email client, it allows you see emails and create emails. It can scan for 'Junk' but you would need to make sure your Junk Controls have been set up correctly. See info here:

By default, Thunderbird blocks remote images and other content in messages from people you don't know. This protects your privacy because spammers can verify your email address by detecting if you viewed a remote image in a message from them. Its also possible to embed an executable (malware) in images. When you receive a message with remote images, Thunderbird will display an alert stating that remote images have been blocked, and the images in the message body will be replaced with simple place-holders

So do not click on links or images or open attachments from anything that looks suspicious. Do not allow remote content in any email that is not from a known and trusted source.

Modified by Toad-Hall

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Just had a thought....Are you using Windows 8 ? Because Defender changed with version Windows 8. Microsoft claim with Windows 8 it takes on viruses and malware. So I presume it must be able to scan incoming emails.


It is also possible that you have other software performing auto checks and updates, like Windows or Adobe. I usually set these up to check for updates but not actually install until I say, then I can update after checking email.

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If you are running Windows 8 or 8.1 then this link has some good helpful info regarding Defender.

you can prevent Windows Defender from scanning certain files and locations (folders), file types and processes. In 'Settings', there is 'Excluded files and Locations' link. This link has some good helpful stuff on this particular point.

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Thank you, I checkered as you instructed and It is a POP email system.

I do have windows 8 , I do not know if it is 8.1 , I got the computer, HP Pavilion last summer.

Yes, I set things when I can to ask me before updating, However windows knida forces it's update on me. Screwing up my Excel every time. but that's another issue

I never know what is the best free malware tool , is it avast? Or do I not need it now that I have the windows 8 version of Defender?

Sorry for the late response , In the middle of work, I work from home , I have a lot more to do today but will look at the links you sent me asap.

I Very much appreciate your help, But I get lost with the tech stuff to easy.

I was hoping it would be a simple fix. My old outlook used to keep downloading deleted email over & over again which was horrible, So TB is way better in this and other regards.

A little white out & lock up once or twice a day does not seem like such a big problem any more. it is fairy consistent.

Do you work for Mozilla or are you just kind person trying to help?

        Again , Thank you SO much.
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No, I do not work for Mozilla, I'm just someone who uses Thunderbird and helps out others in my free time.

If you are wondering which folders/files to exclude from scanning.

Profile folders should be located at directory below, but you may need to make hidden files and folders visible in order to see them.

C:\Users\Windows user name\AppData\Roaming\Thunderbird\Profiles\Profile name

The AppData folder is folder is a hidden folder; to show hidden folders, open a Windows Explorer window and choose "Organize → Folder and Search Options → Folder Options → View (tab) → Show hidden files and folders".