When emails are sent, there is a call to the smtp server, once it has verified username and password are good, the email is now in the hands of the smtp server and it then has to connect with receiving server. However, the server may be forced to try several times to get it delivered. It may also be passed through several servers.

Suggest: You can check the headers of a received email to see when email was sent and the various servers it had to negotiate and the times it was received and sent by those servers. Remember in some cases it may be going through different timezones. Select email so it displays in Message Pane, click on 'More' button and choose 'View Source'. It will open in another window, so you can read the information. The server info nearest and above the FROM, TO, Subject part will be oldest and the server above is the one that receives and sends onward with the top one being the last receiving server.

If Thunderbird connection is not made to server then it fails and does not get sent. You would be aware of that. As emails do get received - albeit eventually, then clearly the email was sent. If sent then it has nothing to do with Thunderbird. It has gone. Thunderbird is not a server, so it is not hanging on to the email.

re :I clicked a "forgot your password" link and it took 24 hours before I got the automatic e-mail....... I already checked with the host and the problem is not with them That email would have going through the necessary servers to get to the server that has the mail account for that email address - which you would only see via webmail. Are you saying you could see that recieved "forgot your password auto email" virtually immediately in the webmail account yet it took another day for Thunderbird to check and download mail, even though Thunderbird was running ?

Only after it has been received by the server can Thunderbird download it.

If you have a IMAP account and if the server support IDLE , newly received emails on server get pushed to your imap account, assuming Thunderbird is running, so you do not need to check very often eg: every 30 minutes as a backup check. Otherwise, Thunderbird connects to check server on startup and periodically depending upon what settings you have set up for the account. But you could check to see if the account is set up to check every eg: 15 minutes. The 'Activity Manager' keeps a log for the session, so you can tell when Thunderbird is checking server.

Please note, if your webmail account is using up it's quota and is hovering around the full quota, then the server cannot receive emails until something has been deleted, once there is space, the server can recieve an email that may have been trying to be sent by another server.

So, please check how many emails are still on the server. POP accounts may not have as much space as IMAP accounts. It might be necessary to remove emails off server. Compacting folders may help to tidy old long deleted stuff to ensure fully removed. IMAP accounts should show you quota percentage via right click on Inbox folder and select 'Properties' and then select 'quota' tab.

Some servers have an automatic delay in sending, but not that long eg: gmail and outlook allow a short delay just in case you want to cancel.

Servers do set limits on the number of emails that can be sent within a given time frame and this varies between servers and the package you may have purchased. Therefore some people/business's use a 'Send Later' method which may have a schedule of when to send emails. This means they can be sent in batches, so server is happy.

If the email server is being used to take on large bulk emailing jobs, your delivery rate would suffer and you would inevitably clog your bandwidth and potentially delay sending and receiving peer-to-peer emails. So, even this might be the cause, but Thunderbird is not involved with what a server can or cannot do.

Hello,

1. About view source: it's delayed immediately when being sent, I think. This is a part from what I got: Received: from CJEXCH06.AD.CURIA.EUROPA.EU ([fe80::2148:cbf8:83b0:1a9d]) by

CJEXCH06.AD.CURIA.EUROPA.EU ([fe80::2148:cbf8:83b0:1a9d%5]) with mapi id
15.01.2176.012; Thu, 27 May 2021 12:03:15 +0200

From: FreelanceNL <[email protected]> To: Sara Reyniers <[email protected]> Subject: =?Windows-1252?Q?DDP=5FRES___C-279/21_=96_EN_(pivot)=96_circa_13_blz._=96?=

=?Windows-1252?Q?_09/06.?=

Thread-Topic: =?Windows-1252?Q?DDP=5FRES___C-279/21_=96_EN_(pivot)=96_circa_13_blz._=96?=

=?Windows-1252?Q?_09/06.?=

Thread-Index: AddS33Qp4Enk62zJQnSD1To3c6oO8w== Date: Thu, 27 May 2021 10:03:15 +0000

-> Does that mean it's my server (in other words my webhost)?

2. Thunderbird is running and my server settings in Thunderbird are OK: it checks every few minutes. I seem to receive the mails in the webmail from the host at the same time.

3. I think the quota or server limits might be the cause, but how can I check that?

This bit was when it was initially sent: Received: from CJEXCH06.AD.CURIA.EUROPA.EU ([fe80::2148:cbf8:83b0:1a9d]) by CJEXCH06.AD.CURIA.EUROPA.EU ([fe80::2148:cbf8:83b0:1a9d%5]) with mapi id 15.01.2176.012; Thu, 27 May 2021 12:03:15 +0200

which is the same date/time as: Date: Thu, 27 May 2021 10:03:15 +0000

Just a different timezone.

But was there some more 'Received:' sections above the one you mention which should state which servers it was passed through and the top one would be the receiving server for your webhost account?

re:3. I think the quota or server limits might be the cause, but how can I check that? If you have an imap account in Thunderbird then right click on the 'Inbox' folder and select 'Properties' Under the 'quota' tab, it would state how much you have used.