Black Friday is supposed to get its name from the profit-friendly color it brings to merchant balance sheets. Microsoft's Live Search Cashback program came up with an embarrassingly different definition for the term. When a shopping search engine is unavailable for several hours on the biggest shopping day of the year, that's a Black Friday indeed.

The Cashback site seems to have been swamped because of a promotion it had for Hewlett-Packard computers. The 40%-off deal on some HP models drove a lot of traffic. Some users got no response from the Cashback site; others managed to complete their purchases but got only a 3% cash-back deal. Microsoft has asked customers who were affected by the Friday fumble to contact the company.

On Monday, Microsoft tried to dull the pain of downtime and rebate glitches by offering a new deal that gives immediate cash back for certain eBay purchases. The curious part is that not all users are eligible for immediate cash back, and eligible users won't be notified of their luck until after the purchase is made. It's like buying a lotto ticket, and may pay out just as often. In the meantime, lotto losers will be stuck with the 60-day waiting period plus another two-week wait after you pretty-please them to send you the money.

As Microsoft works to build its Azure cloud-based service architecture, the last thing it needs is an outage like this to sully its reputation. No, Live Search Cashback isn't built on Azure; nothing is built on Azure at this point. Yet if Microsoft can't design an architecture to keep its own services going under heavy load -- whether Azure-based or not -- how can customers be expected to trust Microsoft's services to host their own needs?