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How do I adjust the number of connections to the server. I get rejected after three connections.

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  • 17 have this problem
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  • Last reply by Adcan

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The following message appears after I have accessed three 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."

The following message appears after I have accessed three 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."

Chosen solution

You can connect to a IMAP server as often as you want, BUT... you may be restricted in the number of simultaneous channels that are open during that connection.

Thunderbird sets a default limit of 5. You can go higher on some servers, or you can go as low as 1. Try setting the connection limit to 3


'Tools - Account Settings - [select your account] - Server Settings - [Server Settings section] - Advanced - Maximum number of server connections to cache - [Enter 3] If it is already set to 3, go lower - 2 or even 1. OK out

TB-38.2 Win-PC

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Chosen Solution

You can connect to a IMAP server as often as you want, BUT... you may be restricted in the number of simultaneous channels that are open during that connection.

Thunderbird sets a default limit of 5. You can go higher on some servers, or you can go as low as 1. Try setting the connection limit to 3


'Tools - Account Settings - [select your account] - Server Settings - [Server Settings section] - Advanced - Maximum number of server connections to cache - [Enter 3] If it is already set to 3, go lower - 2 or even 1. OK out

TB-38.2 Win-PC

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Thank You. The solution worked and now I can access each of the folders. I am very grateful for your assistance.