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How to downgrade Thunderbird 64 bit to 32 bit

  • 13 replies
  • 1 has this problem
  • 2 views
  • Last reply by nancy61

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Hi all, I have two computers both running Windows 10 and both have Thunderbird 78.14.0 but one of computers is running Thunderbird 78.14.0 (64-bit) whilst the other is running 78.14.0 (32-bit). The one running the 32 bit works fine and prints everything no problem but the PC running the 64 bit has a horrible layout and the messages that are saved in the sent folder look different and printing is horrible. Is this an issue with the 64 or 32 bit or is it something that is different in the settings. If I downgraded to 32 bit would that solve the problem ? If so, how to I downgrade Thunderbird from 64 to 32 bit ? Thank you.

Hi all, I have two computers both running Windows 10 and both have Thunderbird 78.14.0 but one of computers is running Thunderbird 78.14.0 (64-bit) whilst the other is running 78.14.0 (32-bit). The one running the 32 bit works fine and prints everything no problem but the PC running the 64 bit has a horrible layout and the messages that are saved in the sent folder look different and printing is horrible. Is this an issue with the 64 or 32 bit or is it something that is different in the settings. If I downgraded to 32 bit would that solve the problem ? If so, how to I downgrade Thunderbird from 64 to 32 bit ? Thank you.

Chosen solution

If you're able to highlight a word and then Ctrl+K to insert a link, you must be composing an html-format message. But if the sent message appears as plain text, you either have the recipient set to receive plain text, or the Send Options are converting the message to plain text. Was this profile used in a version older than 91? If this is just one of many issues, I would test with a new profile, created from Help/More Troubleshooting, about:profiles.

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> Is this an issue with the 64 or 32 bit or is it something that is different in the settings. If I downgraded to 32 bit would that solve the problem ?

There should not be a difference, and so to your second question, I should think not.

I would look for some other reason. Also, maybe post a screen shot showing how it looks

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Hi Wayne, Thanks for your reply. My issue is mainly in the Composing of emails. In this version of Thunderbird when I compose an email and highlight a word such as click here to make it bold or enlarge it. The word here does not appear as bold lettering in the receivers email or in my sent copy. Instead it appears as *here* surrounded by two asterisks. What has changed in the Composition of emails ? Thanks again.

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If it appears as *here*, that is the way plain text messages indicate bold. Check the contact Properties to see if they prefer plain text instead of html, and Send Options in Preferences/Composition/HTML Style. The attached picture shows my settings.

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Hi sfhowes,

Thanks for your reply. Even if I insert a link to the word here it appears as *here* and then the address of the link instead of here being underlined in bold. Just as an example : e.g. please click *here* https://www.support.mozilla.org

Could it be something wrong in the settings ?

Thanks again.

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Chosen Solution

If you're able to highlight a word and then Ctrl+K to insert a link, you must be composing an html-format message. But if the sent message appears as plain text, you either have the recipient set to receive plain text, or the Send Options are converting the message to plain text. Was this profile used in a version older than 91? If this is just one of many issues, I would test with a new profile, created from Help/More Troubleshooting, about:profiles.

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Hi sfhowes, Yep, problem solved. For some reason all the settings in my address book have changed to "Prefer to receive messages formatted as UNKNOWN" I have changed this to HTML. I also downloaded the latest version of Thunderbird (91.1.1) Thanks for your help.

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It looks like I need to downgrade Thunderbird from 64 bit to 32 bit. I'm setting up a new computer with Windows 11 and Quickbooks desktop will not send forms/mail via Thunderbird as it does on the 32 bit version. It sends them directly through Quickbooks so there isn't a copy in Thunderbird. Do I just uninstall the 64 bit one and install the 32 bit version? Does if effect the profile? Many thanks for any help.

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no need to uninstall. just install the 32bit over top 64bit in the "x86" program directory

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Wayne Mery said

no need to uninstall. just install the 32bit over top 64bit in the "x86" program directory

I LOVE this answer. I'd LOVE to not have to do a backup of Thunderbird, etc. I'm not finding HOW to install 32bit OVER the 64 bit, in the x86 program directory. the 64bit won't be IN the x86 program directory, since it's for 32bit programs, correct?

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> the 64bit won't be IN the x86 program directory, since it's for 32bit programs, correct?

incorrect

> I'm not finding HOW to install 32bit OVER the 64 bit, in the x86 program directory.

just run the installer

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Done, but I couldn't find anywhere during the wizard, on standard or custom install, to select 32 but and Thunderbird website doesn't seem to offer it? Only 3rd party apps.....

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Found one!

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https://www.thunderbird.net/en-US/thunderbird/all/#E

Thanks for your help, Weyne Mery!