While this update may not hit everyone, it slammed me hard. The first boot up said mbr_error_1. Then BSOD. The disc structure was so damaged it couldn't see the restoration points. After two days of trying every kind of utility, boot option, restoring partition, etc, I gave up and had to reinstall hundreds of utilities, programs and fonts. It takes about 20 hours just to install what I need on my computer.
The initial alerts didn't specify KB2862330-- in fact it was another update that originally got blamed. I blocked the first update with a warning but this one sneaked back in the group (original installation discs means hundreds of updates). Same thing happened again. Another 20 hours of installation and several more hours identifying all the possible causes. Before the second installation I found a list of all the 10-8-13 updates and have been blocking them as they come up.
My boot disc doesn't have any data on it. But, the programs were affected twice in a period of 10 days and still MS has this nasty thing on the download list. And still they don't have a cure for it. The safest thing anyone can do is not accept any 10-8-13 update. No one knows if the issue is a combination of updates, just this one update, is it related to USB3 ports?