A few of our Mozilla Thunderbird e-mail client users didn’t have their IMAP account setting set to “Use secure connection (SSL)”. It’s an easy enough change to make, just a single check-box, usually anyway. Unfortunately, one of our users would make the change only to get this error box pop-up:

Alert: Could not initialize the browser’s security component.
It was followed by another error box saying that SSL was disabled.
I did a search on Mozilla’s site, with no reference to this error. Google gave me only one reference that there was probably something wrong with the user's Thunderbird profile certificates, probably due to Thunderbird having imported from a previous Netscape 6 or 7 profile.
So, I closed out Thunderbird, went into that user’s Thunderbird profile folder and moved out the cert8.db file. That appears to have done the trick.
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