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TB in my laptop: "Unable to connect to IMAP server. You may have exceeded the maximum number of connections to this server...."

  • 2 replies
  • 4 have this problem
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  • Last reply by JamieEff

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The following message appears after I have accessed several folders in my email.- "Unable to connect to IMAP server. You may have exceeded the maximum number of connections to this server. If so, use the Advanced IMAP Server Settings dialog to reduce the number of cached connections."

I saw the same question posted somewhere and following the solution suggested, I decreased the # of cached connections to 3, then, 1, but this did not solve the problem. TB seems to keep trying to download new emails and never finish. At my TB, I have 2 gmail accounts and 4 or so accounts with other email account server, all IMAP, not POP.

I also went to web gmail sites and deleted substantial amount of old emails. It did not make any difference.

My smartphone received new emails with no problem. The problem occurs only with TB in my laptop.

Please help!

The following message appears after I have accessed several folders in my email.- "Unable to connect to IMAP server. You may have exceeded the maximum number of connections to this server. If so, use the Advanced IMAP Server Settings dialog to reduce the number of cached connections." I saw the same question posted somewhere and following the solution suggested, I decreased the # of cached connections to 3, then, 1, but this did not solve the problem. TB seems to keep trying to download new emails and never finish. At my TB, I have 2 gmail accounts and 4 or so accounts with other email account server, all IMAP, not POP. I also went to web gmail sites and deleted substantial amount of old emails. It did not make any difference. My smartphone received new emails with no problem. The problem occurs only with TB in my laptop. Please help!

All Replies (2)

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Your smart phone is most probably a iDevice as they appear in dispatches most often. Apple in their wisdom do not offer the ability to throttle the number of connections, but they do make use of them the same way Thunderbird does. It makes things faster.

Unfortunately the Apple devices consume ALL available connections to the server unlike Thunderbirds limit of 5 they have no limit, until the server refuses further connections, and other devices get left with an error message. To fix the issue turn off your phone.

If you find a way to throttle the connections from your phone please post it. Your one of may who have issues and no resolution from Apple. Many like yourself are unaware that the device that appear to be working is the root cause.

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This is happening to me on my laptop (win 10). workign fine on the desktop (also win10) and have turned off my iphone.....

is there anything else that can be done?