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On Start up Thunderbird locks up with "Not responding" if anything is selected

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  • Last reply by Ed

rrambrose
rrambrose
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Thunderbird has become a pain now for a number of months- regardless of any updates. On first start up if I click on anything on Thunderbird before ALL email accounts have completely finished downloading, Thunderbird locks up and displays not responding on the top of the screen. I have to wait ten minutes and longer before I can start reading a email until every email on every email account has finished downloading. When a site says it is sending a verification email - before I can see that email when I start Thunderbird - the verification email needs to be resent because it has run out of time. This never happened a year ago - now it is daily! I don't know what Mozilla is doing to Thunderbird but it is now highly unreliable! If it was not the only free email client software I would have dumped it by now. Why is it doing this?

Thunderbird has become a pain now for a number of months- regardless of any updates. On first start up if I click on anything on Thunderbird before ALL email accounts have completely finished downloading, Thunderbird locks up and displays not responding on the top of the screen. I have to wait ten minutes and longer before I can start reading a email until every email on every email account has finished downloading. When a site says it is sending a verification email - before I can see that email when I start Thunderbird - the verification email needs to be resent because it has run out of time. This never happened a year ago - now it is daily! I don't know what Mozilla is doing to Thunderbird but it is now highly unreliable! If it was not the only free email client software I would have dumped it by now. Why is it doing this?

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christ1
christ1
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What is your anti-virus software?

rrambrose
rrambrose Question owner
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christ1 said
What is your anti-virus software?

Windows Defender

Ed
Ed
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Try adding exclusions in Windows Defender for the TB executable and the TB Profiles folder: 

- in Windows, click Start and type: virus

- click Virus & threat protection System settings > Virus & threat protection settings > Manage settings

- scroll down to Exclusions > click 'Add an exclusion' > File

- navigate to and select the Thunderbird.exe file (usually in C:\Program Files\Mozilla Thunderbird folder) > click 'Open'

 - to locate the executable: 

 - TB menu > Help > Troubleshooting Information

 - Application Basics section > 'Application Binary'

- click 'Add an exclusion' > Folder

- navigate to and select the Thunderbird Profiles folder (all profiles - usually at C:\Users\<username>\AppData\Roaming\Thunderbird\Profiles) > click 'Select Folder'

   - to locate the Profiles folder:

 - TB menu > Help > Troubleshooting Information 

 - Application Basics section > scroll down to 'Profile folder > click the 'Open Folder' button

 - navigate up two levels 

IMPORTANT: go to TB menu > Settings > Privacy & Security > Security > Antivirus and enable 'Allow antivirus clients to quarantine individual incoming messages'.