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MS365 mail slow and sometimes doesn't download for hours

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  • Paskiausią atsakymą parašė sfhowes

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I have 4 email accounts in Thunderbird. Only one is MS365 mail. The others work just fine, but the MS365 account frequently stops downloading emails, sometimes for many hours. Then they are all dumped at once, no matter how many times I manually ask to get mail. This is a POP account. I have tried clearing cache, removing extensions. Nothing seems to work. The same emails download seamlessly into Outlook but I don't want to use Outlook! Any ideas to solve this?

I have 4 email accounts in Thunderbird. Only one is MS365 mail. The others work just fine, but the MS365 account frequently stops downloading emails, sometimes for many hours. Then they are all dumped at once, no matter how many times I manually ask to get mail. This is a POP account. I have tried clearing cache, removing extensions. Nothing seems to work. The same emails download seamlessly into Outlook but I don't want to use Outlook! Any ideas to solve this?

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Hey there! It sounds like you're facing a frustrating issue with your MS365 email account in Thunderbird. The fact that the other accounts work fine suggests this is specific to the MS365 account. Since you've already tried clearing cache and removing extensions without success, let's try a couple more things. First, double-check your email server settings for the MS365 account. Make sure they're correct and up-to-date. Also, try creating a new profile in Thunderbird and adding only the MS365 account to see if the issue persists. If it doesn't, it might be related to your existing profile. Lastly, check if there's any firewall or security software that might be causing delays.

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I have confirmed the settings and checked (turned off) security to test. Email does arrive....it just arrives at random times and sometimes many hours after sent. I don't know that I can create a new profile on the same PC with the same email address but will try. BTW, two other colleagues with the same MS365 account are having the same issues. This seems to be some sort of issue with MS365Thunderbird communication...has anyone else seen this?

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Turning off or disabling security/antivirus is not as effective as running Windows in safe mode, which bypasses startup apps like AV, VPN etc. Also, state if your account is a domain O365 account or a consumer hotmail/outlook.com/msn type account, and post the server settings, as in this topic.

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Attached are the settings. Not sure how windows safe mode will help since I can't continue to always operated in safe mode. And, whatever may be "interfering" is ONLY interfering in the 365 account. Gmail and Google workspace accounts work just fine. LMK if you see an issue with the settings. Thanks.

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Windows safe mode is a means of testing the effect of startup apps on TB performance; it's not intended to be a permanent working mode. Your POP settings are correct for the incoming server, although setting the polling frequency to something like 10 mins. or more might have a positive effect. If you are concerned about getting immediate notifications of incoming mail, IMAP is a better option. Also, if you are accessing the account with multiple mail apps or from different devices, IMAP is preferred.

You can add the account as IMAP without removing the POP account, but disable the checking settings in the POP account to see how the IMAP account performs.

The IMAP settings are the same as for POP, except the port is 993. (You can't change from POP to IMAP by changing the port; add the IMAP as an existing account.)