Try not to get frustrated! Try to run the lastest Verizon.

Earlybird corresponds to an alpha release and is strictly intended for testing purposes only. It is by no means recommended for production use. This is what I'd do: First create a full backup of your profile. http://kb.mozillazine.org/Thunderbird_:_FAQs_:_Backing_Up_and_Restoring

Then uninstall Earlybird.

Download the current release version from https://www.mozilla.org/en-US/thunderbird/

Install the release version.

Report back if you still having problems.

In case you want to stick with Earlybird you can download the latest version here: https://www.mozilla.org/en-US/thunderbird/channel

If you know what you're doing you can also install the release version alongside with Earlybird. In that case make sure to create a separate profile for the release version and make sure not to mix-up profiles. If that sounds too complicated, better forget about it.

Earlybird is the name of one of four main development channels. The equivalent for Firefox is Aurora.

Release, Beta (b#), Earlybird (a2) (Aurora for Firefox) and Daily (a1) (Nightly for Firefox).

Thanks, all. Any comments on this?

http://www.techsupportalert.com/best-free-windows7-vista-64-bit-software.htm?page=0,7

"Thunderbird is our recommended client for the 32-bit Windows desktop but Mozilla's only 64-bit version is the unsupported beta Earlybird. It is good enough to use but be warned that you may strike problems although I haven't ... yet.

Unfortunately, moving from your existing email client to 64-bit Thunderbird 3 can be quite a challenge."

And what do they mean by 64-bit Thunderbird 3??

Why do you want or need a 64 bit version in the first place? Also see http://kb.mozillazine.org/64_bit_builds

And what do they mean by 64-bit Thunderbird 3??

You should ask them.

Sorry if I wasn't clear. When I first tried TB, and it crashed, I Googled for a solution, and found a recommendation to try EB specifically because it was designed to work on a 64 bit system. As I said, that was some 18 months ago, so perhaps the latest version of TB will work - although the system requirements still say that 64 bit systems are not supported.

I have now backed up my profile (MozBackup) and I'll try to install TB later.

I Googled for a solution, and found a recommendation to try EB specifically because it was designed to work on a 64 bit system.

So you followed some questionable advice installing an alpha version for production use. And you didn't fix the underlying problem at that time.

the system requirements still say that 64 bit systems are not supported.

It says there are no official 64-bit Thunderbird builds. The 32-bit and 64-bit versions of Windows Vista and Windows 7 can both be used to run (32-bit) Thunderbird.

I've uninstalled EB, installed the latest TB and it seems to be working fine - so far! it even picked up my profile and E-mails without a restore.

Thanks again for your help.

When your problem has been fixed can you mark the thread as 'Solved' please? Thank you.

I see now you already did.

There is not even any Win64 Release of Firefox yet from mozilla.org so there will not likely be any Win64 Thunderbird Releases until after if ever as the Thunderbird community is only so able.

The earliest that there may be Win64 Firefox Release may be Firefox 38.0 even though there are automated builds of Win64 Firefox for 37.0b2 and on currently.