[WinPartners] Excel 2007 calculation display hotfix available for download

[alexander kozlov]

Good Morning,

Information Services & Technology (IS&T) would like to notify MIT computing
community that Excel 2007 calculation display hotfix is now available for
download. The Excel calculation display bug hotfix and links were osted on
the Excel team blog last night on
<http://blogs.msdn.com/excel/archive/2007/10/09/calculation-issue-update-fix
-available.aspx>

The posting is also copied below:

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:
http://download.microsoft.com/download/6/1/3/61343075-aa12-4152-a761-fccc16d
6cef4/office-kb943075-fullfile-x86-glb.exe
64-bit Excel Services 2007:
http://download.microsoft.com/download/c/d/c/cdcccd84-86cd-4199-b01c-1df2dac
66534/office-kb943076-fullfile-x64-glb.exe
32-bit Excel Services 2007:
http://download.microsoft.com/download/c/d/c/cdcccd84-86cd-4199-b01c-1df2dac
66534/office-kb943076-fullfile-x86-glb.exe

KB Articles have been posted as well:
Excel 2007: http://support.microsoft.com/default.aspx/kb/943075/ 
Excel Services 2007: http://support.microsoft.com/default.aspx/kb/943076

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

Explanation of the issue is posted here:
http://blogs.msdn.com/excel/archive/2007/09/25/calculation-issue-update.aspx
 
Calculation Issue Update

Yesterday we were alerted to an issue in Excel 2007 (and Excel Services
2007) involving calculation of numbers around 65,535.  The Excel team would
like to provide a description of the issue and explain what we're doing
about it. 

Background

Yesterday evening we were alerted to an issue in Excel 2007 (and Excel
Services 2007) involving calculation of numbers around 65,535.  The first
example that we heard about was =77.1*850, but it became clear from our
testing as well as additional reports that this was just one instance where
Excel 2007 would return a value of 100,000 instead of 65,535.  The majority
of these additional reports were focused on multiplication (ex. =5.1*12850;
=10.2*6425; =20.4*3212.5 ), but 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.  This issue only exists in Excel 2007, not
previous versions.

The Problem

This issue was introduced when we were making changes to the Excel
calculation logic in the Office 2007 time frame.  Specifically, Excel
incorrectly displays the result of a calculation in 12 very specific cases
(outlined below).  The key here is that the issue is actually not in the
calculation itself (the result of the calculation stored in Excel's memory
is correct), but only in the result that is shown in the sheet.  Said
another way, =850*77.1 will display an incorrect value, but if you then
multiply the result by 2, you will get the correct answer (i.e. if A1
contains "=850*77.1", and A2 contains "=A1*2", A2 will return the correct
answer of 131,070).
So what, specifically, are the values that cause this display problem?  Of
the 9.214*10^18 different floating point numbers (floating point on
wikipedia) that Excel 2007 can store, there are 6 floating point numbers
(using binary representation) between 65534.99999999995 and 65535, and 6
between 65535.99999999995 and 65536 that cause this problem.  You can't
actually enter these numbers into Excel directly (since Excel will round to
15 digits on entry), but any calculation returning one of those results will
display this issue if the results of the calculation are displayed in a
cell.  All other calculation results are not affected.
T
he Solution

We take calculation in Excel very seriously and we do everything we can in
order to ensure that calculation is correct for all cases.  We've come up
with a fix for this issue and are in the final phases of a broad test pass
in order to ensure that the fix works and doesn't introduce any additional
issues - especially any other calculation issues.  This fix then needs to
make its way through our official build lab and onto a download site - which
we expect to happen very soon.  We'll add another post once that's taken
place with a link to the download.




Alexander Kozlov
Windows Platform Coordinator
Software Release Team
Information Services & Technology
MIT
N42-250C, Cambridge, MA 02139

Tel  (617) 253-5103
Fax (617) 258-8736