Excel should come with a cigarette pack warning label: “If you are at risk of a heart attack, please refrain from using this product” or “This product increases your risk of complete mental breakdown”. Bright red letters. Skull and crossbones. Larger than the name of the product itself. Flashing, perhaps.
I honestly don’t know how Microsoft charges money for a p.o.s. program like Excel. More accurately, I’m baffled that we keep buying it. Nothing I do will change the fact that even if I start with a brand new spreadsheet and manually type the dates in, it will invariably screw them up. It’s like some sort of universal constant like the speed of light, earth’s gravitational pull, or Kanye being prone to douche-baggery. It completely makes random, arbitrary decisions on what a date is or isn’t no matter what you TELL it to do. If you type 30/11/09 it’s General, if It’s 4/11/09 it’s a date. And holy ol’ jumpin’ Jesus on a crutch, even if you do get it working in Excel, wait’ll you try importing that sucker into SQL Server. Bravo, Microsoft. Bravo. Top talent at work there.
You can literally spend more time searching for a solution than it would to actually resigning yourself to sitting down and typing the whole thing into the damn database by hand.
Thankfully, I rarely have to touch Excel. But even these occasional brushes with it force me to eject my spleen like the Enterprise ejecting it’s about-to-explode warp core (had to have a geek references for my nerdly brutha’s and sista’s out there).

I can sympathize. Date formats are a wild and woolly thing in Excel. But, I must say that for slicing and dicing data in easy to read ways, there’s just no substitute. Once you quit fighting it, it gets easier. Besides, you keep buying it because your company’s average financial bean counter can make Excel sing….