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I can't send a tiny email to myself on Thunderbird, but I can do it using Outlook
Using an IMAP connection to a Microsoft Exchange account, I get the message
The size of the message you are trying to send exceeds a temporary size limit of the server. The message was not sent; try to reduce the message size or wait some time and try again. The server responded: 4.3.1 Insufficient system resources.
But I can send it with Outlook/webmail, so it isn't a server problem.
Edeziri
All Replies (1)
The 4.3.1 error-message came from the server, telling Thunderbird it couldn't comply. The fact that you could send it using webmail isn't proving much. Webmail use a http or https- protocol and mail-clients like TB use smtp. They also are using different server-engines, addresses and ports.
To diagnose problems with Thunderbird, try one of 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 10, Windows 8, Windows 7, Windows Vista, Windows XP, OSX
- If safe mode for the operating system fixes the issue, there's other software in your computer that's causing problems. Possibilities include but not limited to: AV scanning, virus/malware, background downloads such as program updates.