No. you can not. Given you have posted three questions all about similar issues and none with much information, you might want to try asking your mail provider what is the problem with their mail server.

https://support.mozilla.org/en-US/questions/1227669

No idea, what mail provider is it that you are having issues with? (It sounds a little yahoo like (including ATT) but that is just guessing) Do you use an anti virus? Does it scan mail? Is the result different if you turn off the mail scanner?

Yes I have submitted 3 questions about the same situation. Background: I shut down TB in the middle of a download after I had switched account setting from Leave on Server to Don't Leave on Server and back to Leave on Server. Since then I have been getting the DELE error message. The account setting switching occurred after I had received a message that a few things (I don't remember the others) including Leaving messages on Server. First reaction was to change the setting, but when I started seeing all the e-mails being downloaded again, and probably being deleted from the server, I hastily shutdown TB and changed the account setting back to leave mail on the server (where it had been for years and was working well.) Now when I open TB and it checks mail I get the error message. All mail appears to be still on the server and I receive and send e-mail from the server. The server is ATT/Yahoo. Avast is the anti virus and it had been scaning e-mail for years.) Currently Avast tray icon is indicating that "You are Not Protected." There is the message "UI did not Load. AV service is not responding." The only component of Avast that is ON is the Firewall. It appears that Avast is not screening e-mails at this time and checking e-mail results in the DELE error message as shown the the following:

The DELE command did not succeed. Error marking a message as deleted. Mail server inbound.att.net responded: Too many requests.

If you ask I can send TB troubleshooting info (copy and paste into this message?)

I do not think the troubleshooting information will help. The DELE command is issued each time an email is to be removed from the mail server. The only things I can think of to stop the process would result in a complete download all over again of all mail still on the server.

If you delete the popstate.dat file for the appropriate folder in your profile that should "reset" Thunderbirds knowledge of mail on or expected to come off the mail server. It might also be a good time to set the setting to remove the mail from the server as you would be starting fresh. Go to the troubleshooting information. Click the show button for the profile. Close Thunderbird (it reacts badly to you deleting files while it is running) In file manager open the mail folder and then the folder for your yahoo account (if you have had or tried to add more you could have a lot of yahho1 yahoo2 etc. ) delete the popstate.dat file Restart Thunderbird to re-download all mail on the server inbox.

An alternative would be to add the account to Thunderbird as IMAP, but again the messages will download unless you turn off the setting in Account settings > synchronization and storage to keep a copy of the message locally. That would then only download the headers to populate the list and you could delete or whatever from ALL your Yahoo folders. IF you do not want to use IMAP long term, you could remove the imap account once your housekeeping was done.

Thank you Matt for your reply. You mention resetting the setting to remove mail from the server. Wouldn't this make it impossible to handle the mail from the web when I am not at my computer for this POP3 account except for new mail?

What would be the value of creating the account as IMAP? The only advantage that I am aware of is that the folders I create on my computer to hold the mail are duplicated on the server. Since I don't have any devices to manage mail except my computer (which I am at most of the time) having the TB folders duplicated on the server is only a minor convenience.

Downloading all the messages from the server will create a huge number of duplicate messages. What Add-On would you recommend to delete the duplicate messages?

Thank you, Neil