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firefox certificate invalid at Xfinity online.

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I have Firefox 115.1.0esr on Windows 7 desk top PC. When I try to log in to my Comcast Xfinity online account they say my browser certificate is invalid and I can't log in. Any suggestions? Thanks

I have Firefox 115.1.0esr on Windows 7 desk top PC. When I try to log in to my Comcast Xfinity online account they say my browser certificate is invalid and I can't log in. Any suggestions? Thanks

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Hi, it's not your browser's certificate.

Many users have reported a connection problem on a page with an address at idm.xfinity.com -- Xfinity's various other servers work fine. Unfortunately, this is a problem on the server (or in their Content Distribution Network) where it looks like someone forgot to update a certificate.

Firefox may be the last browser that does a real-time check for whether a site certificate has been revoked, so it is the first affected by this kind of problem. Firefox doesn't have a way to exempt one site from this check; it is all sites or no sites. For that reason, if you are okay with checking your email in another browser for a while, that probably is safest, rather than me describing how to turn off certificate revocation checking globally.

A couple other things you could look at:

(A) Purge Firefox's web content cache to remove possibly conflicting files. See:

How to clear the Firefox cache (only select Cached web content, don't clear all cookies and site data)

If you have a large hard drive, this might take a few minutes.

(B) Try using one of these URLs to access your Xfinity mail

Direct email link: https://xfinityconnect.email.comcast.net/

New hub page: https://www.xfinity.com/hub/ -- toward the upper right, there's an account button (looks like a little head and shoulders in a circle) that opens a panel to sign in. Any luck using the "Check Email" link on that account panel?

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Thanks jscher, I've been over resetting, testing everything etc with Xfinity. They first said they didn't see a problem at my end then the next day they said it appears to be a problem with Firefox. After trying all these things ( including everything you sent - Thanks) maybe it is just a problem with Firefox certificates and they will correct it if I wait a few days. I don't have another browser. I may load Chrome if it will run on Win 7. Thanks for your reply.

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If you don't have another option, the following thread has the steps to disable checking whether a certificate was revoked. You might only need to use it while signing in, so you could limit your exposure. See:

https://support.mozilla.org/en-US/questions/1420935#answer-1596982