Bypassing the warning
You can tell Firefox to bypass these certificate warnings. You should only bypass the warning if you're sure that the site is legitimate. Legitimate public sites will not ask you to do this. An invalid certificate can be an indication of a web page that will defraud you or steal your identity.
On the warning page, click Or you can add an exception....
Click Add Exception.... The Add Security Exception dialog will appear.
Click Get Certificate.
Read the text describing the problems with this site.
Click Confirm Security Exception if you want to trust the site.
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