We’ve all been there: One missed keystroke, and you accidentally wipe out tons of important data. But chances are your error didn’t result in a lawsuit.

That’s exactly what happened to the lawyers representing Barclays Capital in its recent takeover of Lehman Brothers.

A first-year associate with the firm was asked to reformat an Excel spreadsheet listing assets that would be transferred as part of the deal. But the lawyer, working on tight deadline and under intense pressure, wasn’t familiar with Excel. And when he “resized” the spreadsheet, he inadvertently included 179 assets that were listed in a “hidden” portion of the spreadsheet.

No one caught the error, and the assets were incorrectly included in the final agreement.

Now, the companies have to file a motion with the court to exclude the “new” items.

Just goes to show: You can’t send an attorney to do the work of an accountant — unless you’re OK with its really getting screwed up.

Tags: Accounting, Error prevention, Excel, Lighter side, Spreadsheets, Technology