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Thunderbird cannot open an email & has an error code: ssl_error_no_cyher_overlap. I cannot get out of the Alert message to even delete the message???

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  • Last reply by Tonnes

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Thunderbird is trying to open an email - but I get an Alert that says:

An error occurred during a connection to images costco-static.com443 Cannot communicate securely with peer: no common encryption algorithem(s). (Error code: ssl_error_no_cypher_overlap)

At the bottom of the screen it reads: Checking mail server capabilities - and its just keeps running

I cannot X out or hit OK in the Alert - I cannot get out of this loop to get back to my Inbox to delete the message????

HELP!!!!!!

Thunderbird is trying to open an email - but I get an Alert that says: An error occurred during a connection to images costco-static.com443 Cannot communicate securely with peer: no common encryption algorithem(s). (Error code: ssl_error_no_cypher_overlap) At the bottom of the screen it reads: Checking mail server capabilities - and its just keeps running I cannot X out or hit OK in the Alert - I cannot get out of this loop to get back to my Inbox to delete the message???? HELP!!!!!!

All Replies (3)

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Please have a look at this question (pointing to this question). You should be able to enter the server name from the error message in the security.tls.insecure_fallback_hosts preference using the Config Editor (Options > Advanced panel > General tab), and then restart Thunderbird.

If that helps, perhaps you should notify the email provider about the error. I would also make a note of the edit you made for reference, and reset the preference now and then to see if they solved the issue.

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I can get to about:config and to the "security.tls.insecure_fallback_hosts" but what do I enter as a SERVER name??? The error message contained 3 lines: An error occurred during a connection to images.costco_static.com443 Cannot communicate securely with peer: no common encryption algorithem (Error code: ssl_error)_no_cypher_overlap)

I have entered images.costco_static.com443 and just costco ???? And restarted Thunderbird each time - but the problem is still there?? Thanks for your help.

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Based on your report, it should be the domain name only, so images.costco-static.com - you could skip the port number.

However and before you do: note that Thunderbird is complaining about web content in a message (port 443), not an email server. That’s not bad, but Thunderbird should not "hang" for this reason - I would expect a broken remote image in the message instead.

The validity of the server’s certificate can be checked here. Giving these results, I wonder why Thunderbird should fall back to TLS 1.0. Searching a bit and opening e.g. this picture in Firefox, it works and shows TLS 1.2 is used. (Right-click the page > View Page Info > Security panel)

- Could it be you are running some security software that’s causing this (and perhaps other) issue(s) and if so, what software?

In Thunderbird, you can open the Tools menu (or button) > Developer Tools > Error Console, enable all items on top, click the trash can and see what is reported when trying to load the message.

If that causes trouble, open the Error Console once more, copy the full text line below (from left to right), paste it in the bottom line of the Error Console and press Enter.

Components.classes['@mozilla.org/appshell/window-mediator;1'].getService(Components.interfaces.nsIWindowMediator).getMostRecentWindow('mail:3pane').document.getElementById('tabmail').openTab('contentTab',{contentPage:'https://images.costco-static.com/ImageDelivery/imageService?profileId=12026539&itemId=1160961-894&recipeName=680'})

The GET line should return a [HTTP/1.1 200 OK nnms].
(where "nn" is a response time that can vary.)

You could do the same and replace the https part with any other image URL that uses https and compare the results. If both fail, there may be another issue. Doing as suggested earlier may not even work either, but again, that should not be necessary.

If you think the message is suspicious and not worth doing the above, you could perhaps open webmail and delete the message from there.