Outlook 2007 and Comcast certificate error

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New Member
Outlook version
Outlook 2010 32 bit
Email Account
A friend recently moved from Verizon FiOS to Comcast. She'd like to continue using her copy of Outlook 2007 (in standalone mode on her computer using her previous PST file) on a Win7 machine, but is getting the following message:

"The server you are connected to is using a certificate that cannot be verified.
The target principal name is incorrect. [certificate = mail.comcast.net]
Do you want to continue using this server? yes/no"

She set up her mail connection using her old PST and Comcast's directions (big mistake???) and set things up as IMAP instead of POP3, which is what she was using w/ her FiOS set-up. She can send email, but not receive.

I'm wondering if this is all wrong?

Should she set up Outlook and configure Comcast as POP3 (we understand the idea of IMAP)? Should she use a new PST, and simply copy certain data from the old PST to the new one, particularly if IMAP can't have her calendar, contacts and to-do list?

So far, no one, particularly Comcast (now there's a surprise) knows how to fix the issue.

In other messages here, I have seen reference to installing the certificate (from the message above) onto her machine, but I haven't been able to find any directions on where to get the certificate from.

OR should we chuck the whole thing and install Office365 and use the outlook version that is in there?

Many thanks if you can help us out here........

Diane Poremsky

Senior Member
Outlook version
Outlook 2016 32 bit
Email Account
Office 365 Exchange
The Comcast settings should work... I'm not sure if upgrading will fix the problem or not - I'm guessing not.

What is the server names she is using for incoming and outgoing mail? The message is saying the certificate doesn't match those names.

Incoming Mail Server - imap.comcast.net
Incoming Mail Server - Port Number 993 with SSL ON or 143 with SSL ON
Outgoing Mail Server - Name smtp.comcast.net
Outgoing Mail Server - Port Number 587 (SMTP) or 465 (SMTPS)
SSL Encryption checked

If you want to use pop3, use this incoming server and the same outgoing server that is used for imap.
Incoming Mail Server - Name: mail.comcast.net
Incoming Mail Server - Port Number: 995 (POP3 With SSL) or 110 (POP3 Without SSL)
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