Recently there was an issue with Microsoft Office Excel 2007 that showed a strange symptom during the multiplication calculation. The multiplication formula will show the wrong value when the resultant’s range fall around 65535 and 65536. I wonder how these were discovered as the chance of seeing the problem is like hitting a lottery. Now the new patch has just been released officially by Microsoft to resolve the issue. However, the effect may not be ‘visible’ since most of the users are not really aware of such bugs when using Excel worksheet in daily work.

Not much information was disclosed on the actual root cause but it is suspected to be due to formatting and floating point calculation bug around 65535 and 65566. But why specifically only on these numbers is still unknown. You can try to experiment yourself by multiplying 850*77.1 using excel worksheet. Funny thing is that you won’t get the correct value of 65535 but instead, it will yield 100000.

The patch is downloadable at Microsoft. If you are not sure of the current Microsoft Excel version in your PC, try to follow the simple steps below to check it out. Go to Help Menu, then select “About Microsoft Office Excel” and click on it, you will able to see the version of the Microsoft Excel. There is a plan to put this hotfix into the first service pack of Office 2007 as well as Microsoft Update for future update automatically.