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Server timeout when adding attachment (approx 2MB or more)

  • 5 replies
  • 1 has this problem
  • 3 views
  • Last reply by sfhowes

Joop
Joop
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We have five W10 workstations using Thunderbird 68.8. We have been using TB more then 10 years without problems. Thunderbird updates automatically. Our ISP connection is 14Mbit/sec

When sending a message with an attachment (2MB or more), we get a server timeout message. The message appears when it tries to copy the message to the "sent" folder. I can see the stages when trying to send, like: connecting, identifying, percentages, etc.

The adressee receives the message without problems, but TB does not copy the message to the "sent"folder. It tells me: copying failed due to server timeout. However, sometimes a copy is found in the sent folder despite the error message. Sometimes it is even in the sent folder twice. This is not restricted to one workstation, they all show the same problem.

A message without attachments is sent like lightning. We are using multiple mail-accounts, they have their own SMTPserver. One of them is Gmail

I prepared a workstation with Thunderbird at home (same ISP, higher speed) and it works perfectly. I moved this workstation to the problem site and the problem is there. I reset and reconfigured the router and I made cable connection directly to the router. This didn't solve the problem.

Is connection speed an issue? I expect Thunderbird to work with lower speeds too, it always did in the past; until last year we had 8Mbit/sec.

Any help will be highly appreciated

We have five W10 workstations using Thunderbird 68.8. We have been using TB more then 10 years without problems. Thunderbird updates automatically. Our ISP connection is 14Mbit/sec When sending a message with an attachment (2MB or more), we get a server timeout message. The message appears when it tries to copy the message to the "sent" folder. I can see the stages when trying to send, like: connecting, identifying, percentages, etc. The adressee receives the message without problems, but TB does not copy the message to the "sent"folder. It tells me: copying failed due to server timeout. However, sometimes a copy is found in the sent folder despite the error message. Sometimes it is even in the sent folder twice. This is not restricted to one workstation, they all show the same problem. A message without attachments is sent like lightning. We are using multiple mail-accounts, they have their own SMTPserver. One of them is Gmail I prepared a workstation with Thunderbird at home (same ISP, higher speed) and it works perfectly. I moved this workstation to the problem site and the problem is there. I reset and reconfigured the router and I made cable connection directly to the router. This didn't solve the problem. Is connection speed an issue? I expect Thunderbird to work with lower speeds too, it always did in the past; until last year we had 8Mbit/sec. Any help will be highly appreciated

All Replies (5)

Stans
Stans
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Gmail, Yahoo and Outlook.com outgoing servers automatically place a copy of the sent messages in the Sent folder. This is done on the server side, so it is recommended that you disable this option in Thunderbird for those accounts.

Modified by Stans

Joop
Joop Question owner
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Hi Stans,

Thanks for your reply.

Unfortunately this doesn't solve my problem; three different accounts are used. One of them is a Gmail account, number two and three are neither Outlook nor Yahoo and they all show erratic behaviour.

Stans
Stans
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Sounds like something in your network setup is amiss since you tested another pc at home and it worked just fine, but has problems once on your work place network. I would get your ISP to check things just to be sure everything is working on their end and yours as well. What other hardware/software components are running on your network besides the router/modem; for example, a firewall applicance?

Joop
Joop Question owner
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It's a basic network, not even a domain, it's a workgroup, containing 5 workstations.

There are a few other devices on the network: A small file server (Ubuntu server 16.04) Two printers ADSL modem/router. (ZTE H369A)

ISP says the problem is caused by Thunderbird and they can't help me (and I won't be able to prove otherwise). Connection speed seems to be the major difference between the two sites.

Is it possible to adjust settings in Thunderbird to make it less vulnerable to communication delays? I prefer finding the root cause of the problem, but a workaround would be great.

sfhowes
sfhowes
  • Top 25 Contributor
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It's usually suggested to run Windows in safe mode to test if startup apps such as security/AV are causing timeouts on sending, but if that's not the cause, you could try increasing, e.g. doubling, the mailnews.tcptimeout preference in Options/Advanced/General/Config. editor and see if that has any effect.