LAWTECH GURU BLOG by Jeff Beard

Excel 2007 Multiplication Math Bug

Just when I was about to post how great my experience has been with Office 2007 (I really, really like the new ribbon interface, live format preview, and the enhanced online help), news has been popping up among bloggers and Google Groups of a serious, yet perhaps somewhat specific, math bug in Excel 2007:

If you have Excel 2007 installed, try this: Multiply 850 by 77.1 in Excel.

One way to do this is to type "=850*77.1" (without the quotes) into a cell. The correct answer is 65,535. However, Excel 2007 displays a result of 100,000.

Now the strange thing, according to some posters, is that Excel 2007 treats this result inconsistently when it's used in other formulas dependent upon this result. Sometimes it's used as 100,000, and sometimes it's used as 65,535. On my Vista Ultimate laptop, I was able to duplicate the above poster's test results that reference the above result in cell A1.

As these errors did not occur in Excel 2000 in comparison, this is a step backwards. Let's hope Microsoft corrects it quickly. The question may remain, however, as to what to do with spreadsheets and charts created during the time the bug existed. Assuming MS issues a patch, for critical data it's probably not a bad idea to reopen them after patching and refreshing the calculation to see if anything changed.

My system is current with all relevant patches via Windows Update, which is set to include other Microsoft products such as Office. In Excel's "About" screen, it reports Excel's version as 12.0.6024.5000 and MSO as 12.0.6017.5000. (Presumably, MSO = Microsoft Office.)

If you're having difficulty locating the "About" screen in the new 2007 line, you're not alone. It's buried under the following menu structure:

1. Click on the circular MS Office button at the top left corner in Excel.
2. Click on the rectangular "Excel Options" button near the bottom right corner of the pull-down menu.
3. Click on the "Resources" button (bottom option on the left pane of the "Excel Options" dialog box).
4. Click on the "About" button on the right side of the pane (last one in the list).

So much for the good ol' days of clicking on Help, About, to quickly see version and patch numbers!

On the plus side, overall I've found Office 2007 Professional to be very solid, with substantial usability improvements. As with Vista, which has been getting more reliable with various Windows Updates (e.g., my document preview now works in Windows Explorer), I expect Office 2007 will hit many legal desktops, running either on XP or Vista. Not to mention that more and more third-party software vendors have been making great strides in making their programs compatible and integrated with Vista and Office 2007. There were several Office 2007 readiness sessions at the recent annual ILTA conference, and all were packed with attendees. Many already have test installations well along, and some firms reported they're already receiving documents from clients in the new Office XML formats.

[11.20.07 Update: Microsoft has released an Excel 2007 Hotfix package for this issue.]