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Thunderbird suddenly not working for certain wifi network (my office)

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Hi there,

I am using Thunderbird on a 2011 macbook pro, and everything was just fine until just before Christmas, when I started having issues with Thunderbird being super slow at my office. The same program still works fine at my house. But at the office it now just hangs and spins and times out. I restarted my computer, restarted Thunderbird (several times) and it made no difference. At the office we (tenants) share a Time Warner Cable/Spectrum internet connection that is broadcast with a wifi router. At home I am also on a Spectrum internet connection via a wireless router/cable modem combo.

The only other place I've had this issue is with guest internet access accounts at public universities - where I can surf the web fine but Thunderbird turns up its nose at downloading email. So I assume it is some sort of security setting or another? But what could have changed all of a sudden to make it stop working at my office? I can ask the landlord but it would be helpful to have some idea of what to inquire about (they don't have IT support either I don't think).

The email account in question is an office 365 outlook account: outlook.office365.com, port 993, SSL/TLS, normal password smtp.office365.com, port 587, normal password, STARTTLS connection security

Thank you!

Hi there, I am using Thunderbird on a 2011 macbook pro, and everything was just fine until just before Christmas, when I started having issues with Thunderbird being super slow at my office. The same program still works fine at my house. But at the office it now just hangs and spins and times out. I restarted my computer, restarted Thunderbird (several times) and it made no difference. At the office we (tenants) share a Time Warner Cable/Spectrum internet connection that is broadcast with a wifi router. At home I am also on a Spectrum internet connection via a wireless router/cable modem combo. The only other place I've had this issue is with guest internet access accounts at public universities - where I can surf the web fine but Thunderbird turns up its nose at downloading email. So I assume it is some sort of security setting or another? But what could have changed all of a sudden to make it stop working at my office? I can ask the landlord but it would be helpful to have some idea of what to inquire about (they don't have IT support either I don't think). The email account in question is an office 365 outlook account: outlook.office365.com, port 993, SSL/TLS, normal password smtp.office365.com, port 587, normal password, STARTTLS connection security Thank you!

All Replies (4)

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Have you actually checked with your office?... my guess is they have stopped using TWC/Spectrum.

TWC do require you to use their connection to send mail. The only other thing I can think of for incoming mail is something is blocking port 993 (perhaps a firewall or edge device used by your employer or university.)

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I will check with them tomorrow and see if I can figure out if they made any changes. Thanks!

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Ok, no changes reported by the landlord. And the problem seems to be replicating on a different laptop, at least when I copied my profile over from my old laptop to the new one. The profile transfer seemed to go ok, but the connection to server time is still super slow, as in 5 minutes to send a simple message on 50 Mbps internet, and that only if the server doesn't time out. Anyone have ideas?

To reiterate, the problem goes away at my house, slightly faster internet but I doubt raw speed has much to do with it when we're talking about sending plain text emails.

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Oh and I use the same connection profile at home and at the office - same laptop, Thunderbird has just ceased being functional at the office and I can't figure out why.