Did you solve this?

c-sto said

Since upgrade to 38.0.1 (and no change in SMTP settings), sending POP email from my smtp.bizmail.yahoo persistently fails with: "An error occurred while sending mail. ...Resources temporarily unavailable..." error. Seems to be specific to Yahoo (POP Sonic works fine), but couldn't find any 38.0.1-specific Yahoo-related resolutions (and I didn't encounter any problems with previous TB upgrades). I tried changing the Connection Security settings (as was recommended as a solution for previous issues with that error message), plus several TB re-starts, to no avail. Appreciate any pointers, perhaps even how to revert to previous (last known good) TB version. - Thank you much!

Not yet solved - still an issue

It is a little extra work, but there have been no other reports to go on.

Please clear the error console. Tools menu (alt+T) > error console Open the activity manager. On the same tools menu.

Try and send a mail.

Please post. 1. What appears in the error console. 2. What appear in the activity manager and most importantly 3. A screen capture of the error dialog. (sounds silly but we find a screen captures work better than asking for the error message verbatim.

I would also suggest the following:

• Restart Thunderbird with add-ons disabled (Thunderbird Safe Mode). On the Help menu, click on "Restart with Add-ons Disabled". If Thunderbird works like normal, there is an Add-on or Theme interfering with normal operations. You will need to re-enable add-ons one at a time until you locate the offender.
• Restart the operating system in safe mode with Networking. This loads only the very basics needed to start your computer while enabling an Internet connection. Click on your operating system for instructions on how to start in safe mode: Windows 8, Windows 7, Windows Vista, Windows XP, OSX

Did either safe mode help? The first excludes add-ons and themes and some graphics issues The operating system excludes third party software. Most notably anti virus email scanners, but other boot time software as well.

Hello Matt - thank you for looking into the case, much appreciated.

Re your recommended steps: (1) Cleared TB Error Console - stays blank even though error situation remains

(2) TB with add-ons disabled: error situation remains, TB error console stays blank

(3) Win7Pro Safe Mode: error situation remains. TB Error Console stays blank

I tested every case 3 times, I'm afraid we haven't found the issue yet.

BTW - the error dialog looks like this:

https://help.yahoo.com/kb/SLN17653.html 421 Resources temporarily unavailable. Please try again later. The Yahoo Mail MTAs are temporarily too busy. Your server should try to resend the message after a few minutes.

Lets see if this is version specific or not.

You can get a US EN version of Thunderbird 31 here download and install it.

Sorry but the link was a botch.

Thanks, Matt. TB 31.7 works fine. TB38 still doesn't. Staying with 31 for now with auto-update off.

Haven't fully examined Toad-Hall's Yahoo-Help link yet, but it appears to apply for bulk messages. My error occurs even if I send an email just to myself (i.e. within Yahoo).

It might be to late now, but next time your on 38 to try it. clear the error console. It is on the tools menu and post the entries that appear along with the error message. Often they are more informative. Once you clear out the masses of junk that inhabits that location in the first place.

Re-tried 38 & tested a couple of times - same error/behavior as before. Error console doesn't report anything (see screenshot), sorry.