OK, so version 0.9.27 of "Check and Send" add-on does not work with version 45. Disabling it allowed me to send email. The installer/updater did not catch that incompatibility.

Same problem caused by Quote & Compose manager. I hope it gets resolved soon, I like the Q&C options.

I have this problem, too. Only I don't have that add-on. At least I don't think I do. I went to toos/addons/plugins and it wasn't there. And I have no plugins activated. Please let me know if when there will be an update to this. Thanks

Sorry, I just realized that I have a different problem. Thunderbird lets the message go, but I get a Delivery Status Notification (Failure) when I do. I then send the same email from within Firefox on my gmail account and it goes through no problem. So Thunderbird is the problem. Here's the specific message; Technical details of permanent failure: read error: generic::failed_precondition: read error (0): error

hifromnz said

Same problem caused by Quote & Compose manager. I hope it gets resolved soon, I like the Q&C options.

If you want this resolved then I suggest you let the authors of the problem add ons know so they can fix them.

Major problem for me - having to authorize remote content all over again from my very reliable sources. It's absurd to do that with every one.

Get this one - even from Mozilla.

"To protect your privacy, Thunderbird has blocked remote content in this message." - the message from Mozilla Support of all senders.

Despicable!

For those with Quote & Compose Manager, this is the link to fix Q&C: https://freeshell.de/~kaosmos/index-en.html