Yahoo (NSDQ: YHOO) confirmed reports of major problems with its small business servers during the heart of so-called “Cyber Monday” via a Yodel Anecdotal mea culpa from Rich Riley,SVP-Online Channel Division. With systems back to usual, Riley writes that they are “moving mountains inside Yahoo! to find out why and how this happened, and to take steps to try to ensure it doesn’t happen again.”

So what did happen?  At 6 a.m. pacific Monday, the systems “experienced outages” that continued through roughly 1 p.m., when transactions started to go through. Everything was back up by 6 p.m. That’s the what. The why is another matter, one that Yahoo needs to figure out as the holiday season continues. (A number of users attribute the problems to a new checkout cart.) Ditto for how to provide the right support and communications. Then there’s the issue of compensation.