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I was able to check emails from Comcast yesterday. Now, I can't sign due to the following error: ssl_error_no_cypher_overlap. Need help fixing!

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  • 2 have this problem
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  • Last reply by cor-el

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Whenever, I go to login in on Comcast I continue to receive the following error ssl_error_no_cypher_overlap. All this weekend, everything worked fine and now it does not. Not sure what happened but seeking assistance in fixing the issue. Any assistance is greatly appreciated. Thank you in advance!

Whenever, I go to login in on Comcast I continue to receive the following error ssl_error_no_cypher_overlap. All this weekend, everything worked fine and now it does not. Not sure what happened but seeking assistance in fixing the issue. Any assistance is greatly appreciated. Thank you in advance!

Modified by zwarty

All Replies (4)

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Can you post a link to a publicly accessible page (i.e. no authentication or signing on required) or only the domain?

That would allow us to check the connection to that server. You can also check the domain via this website:


You can check the connection settings.

If you do not need to use a proxy to connect to internet then try to select "No Proxy" if "Use the system proxy settings" or one of the others do not work properly.

See "Firefox connection settings":


Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) to see if that helps.

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Cor-el, here is the link to the website http://my.xfinity.com/?cid=cust.

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Do you log in via this website?

Do you have an "Old Firefox Data" folder on the desktop?

Try to rename the cert8.db file (cert8.db.old) and delete the cert_override.txt file in the Firefox profile folder to remove intermediate certificates and exceptions that Firefox has stored.

If that has helped to solve the problem then you can remove the renamed cert8.db.old file. Otherwise you can rename (or copy) the cert8.db.old file to cert8.db to restore the previously stored intermediate certificates. Firefox will automatically store intermediate certificates when you visit websites that send such a certificate.

You can use this button to go to the current Firefox profile folder: