Friday, January 11, 2008

I am glad Microsoft does not make cars...

What is going on with Microsoft Office Excel? I found an article submitted to Digg which was written based on the article Major bug found in Microsoft Excel 2007 in from 25 of September 2007.

That article gave as a source Major bug in MS Excel 2007 in, where the issue was handled more thoroughly.

The problem was that the calculation 850*77.1 in Excel showed the answer to be 100000. The right answer is 65535.

As a mathematics teacher I got interested and had to give it a try; maybe just not believing my eyes. The articles were right. One suggested that a shell should have SUM(850*77.1) which I find totally unnecessary. I tried using the function giving the product but since I have the Finnish version it looks like TULO(850:77.1). Well, not exactly, we use a decimal comma, not a decimal point. The answer is 100000. I get the same answer if I use the normal “=850*77.1” or if I place the numbers in shells and multiply their content.

However, the number is just rounded up. If I continue and subtract the right answer, as if I was calculating 100000 – 65535, I get 0. The answer is right which means that the content of the shell showing 100 000 is 65535 but Excel hides it from me. With any other numbers in the neighbourhood this does not happen and the calculation 85*77.1 gives me the right answer.

My first impression was that my settings are wrong. I tried to give a more exact answer by taking decimals to the display with the result 100000.000! Even the scientific display failed, now the answer was 1,00E+05. The disturbing thing is that while it was in the form of an integer, one could always claim that it is rounded, but now it shows 3 significant numbers!

The bug was reported at the time and Microsoft Excel blog answers:

our testing showed that this really didn't have anything do to with multiplication - it manifested itself with many but not all calculations in Excel that should have resulted in 65,535 (=65535*1 and =16383.75*4 worked for instance). Further testing showed a similar phenomenon with 65,536 as well.

In 9th of October the same blog finally informs that the update is available:

Calculation Issue Update (Fix Available)

Two weeks ago, we posted about an issue involving the calculation of numbers around 65,535 and 65,536. As of today, fixes for this issue in Excel 2007 and Excel Services 2007 are available for download from the following locations:

Excel 2007:
64-bit Excel Services 2007:
32-bit Excel Services 2007:

KB Articles have been posted as well:

Excel 2007:
Excel Services 2007:

We are in the process of adding this fix to Microsoft Update so that it will get automatically pushed to users running Excel 2007 or Excel Services 2007. Additionally, the fix will also be contained in the first service pack of Office 2007 when it is released (the release date for SP1 of Office 2007 has not been finalized).

Thank you for your patience,

The Excel Team

I bought my laptop one week before Christmas and the Office a couple of days later. I have an Enterprise version licensed for use only by students and faculty. The fix was not automatically pushed to me.

I guess now I have to start downloading… I have not checked yet, if SP1 for Office 2007 is available.


JesieBlogJourney said...

My company software is still using the older version of MS Excel. My home computer has the latest version.

I earn my living by doing a lot of calculation and tests on MS Excel. I have to be accurate in my testing or analysis. I will have to be more careful when I use my own PC for official work.

In auditing I have to deal with many spreadsheets. If I need to work from home, I will use two computers at one time.

I'm going to download the fix. Thanks Leena. Stumbled!

Rob Diana said...


I have found office 2007 to be completely evil. They changed everything about the interface and the file formats. Compared to previous versions, 2007 is also a bit buggy. If you have the option I would recommend going back to a previous version. I do believe that service packs are available now though.

Rampantheart said...

I am using office 2003 and it works just fine.thankfully, i have not tried office xp.moreover, the office pack is nt of much use for me.Anyways, thanks for spreading the info.I have not come across an article about the bugs in office xp.thanks!

HANNA said...

Ciao Leena!
One Award for you in my blog..

Meghna said...

Hi Leena,
Looks like Microsoft shld get to work! I'm glad u spotted the mistake and brought it to notice of all of us!

Keep in touch :D

Gerard Yap said...

Thanks for the tip..will be on the alert ..I'm a firm believer in Microsoft Excel. It has helped me gained credibility at my work. I have also set up a website using real situations and how Microsoft Excel has provided a fast and effective solutions...You have a great blog and keep it up