I haven't met many of these people to ask them, but I know they still exist because of their user agent containing "Windows NT 5.1" and I know for sure they aren't all bots, and many of them even live in Southern California. I suspect these are the people who would be most confused by websites failing to load.

The cost of providing support then is much greater than the cost of a Comodo certificate.

I see. It's a shame you can't intercept the error and display your own along the lines of "upgrade your damn OS already!"

It's not the OS, just Internet Explorer. And an upgrade to the OS isn't free.

Are you sure about that? I assumed it would be affecting SSL verification in WinInet/WinHTTP (and so affect any applications using that stack)...

Please don't do that. Workers at large companies often have no choice

I can sort of understand a handful of rather lazy and/or incompetent users insisting on continuing to use a 15-year-old OS, which was replaced a decade ago, and has not been supported by the vendor for 2 years.

Large companies have no excuse.

Yes, so banning all their employees from buying what your selling seems like a grand idea!

More likely a matter of having a site that has a lot of users who are still running it.

Or an application… Exactly that.