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cannot send mail. Connected to smtp.office365.com but times out.

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  • Last reply by Matt

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I have set up my thunderbird using the information given by office365 outlook. I can receive email fine, but when I try to send email, it says its "connected to smtp.office365.com" and just hangs there, and then says the message could not be sent because the connection to Outgoing server (SMTP) timed out.

How to fix this? Thank you.

I have set up my thunderbird using the information given by office365 outlook. I can receive email fine, but when I try to send email, it says its "connected to smtp.office365.com" and just hangs there, and then says the message could not be sent because the connection to Outgoing server (SMTP) timed out. How to fix this? Thank you.

Chosen solution

Hmm. What a fine line they walk.

StartTLS is actually what the name says. It starts the communication with TLS. SSL/TLS is negotiated on startup. So one gives the other a list of "what I can do" and they pick one in common.

But it is something I will note for the future.

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what anti virus are you using?

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Sorry I got it figured out. I changed security to STARTTLS and it works now, which is strange because the webmail says it's TLS so I used SSL/TLS originally.

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Chosen Solution

Hmm. What a fine line they walk.

StartTLS is actually what the name says. It starts the communication with TLS. SSL/TLS is negotiated on startup. So one gives the other a list of "what I can do" and they pick one in common.

But it is something I will note for the future.