Microsoft KB Archive/151527

= MXL5: Contents of the MS Excel for Mac 15-Digit Read Me File =

Article ID: Q151527

The information in this article applies to:


 * Microsoft Excel for the Macintosh, versions 5.0, 5.0a

SUMMARY

The following information is taken from the "Read Me" text file that is on the "Disk 1 - Setup" disk of the Microsoft Excel 15-digit patch disk set. It contains information about the patch, why you may want it, and how to install it.

MORE INFORMATION
Microsoft Excel Fix for the "15 digit number" Error Microsoft Excel Version 5.0 for the following installations:

68K Macintosh(TM) only Power Macintosh(TM) and 68K Mac dual Power Macintosh(TM) only Thank you for using Microsoft Excel. Along with this readme you should have received the executable file that has been updated to fix the error. The file is in self-extracting Stuffit(TM) format. Depending on which installation of Microsoft Excel you have, one of these three archives have been included with this Read Me:

  Excel68K.sea -or-   ExcelPower.sea -or-  ExcelFAT.sea

Installation Instructions:

1. Prior to installation, make sure that Microsoft Excel is not currently

running. 2. Double-click on the archive located on Disk 1.

3. When prompted for where to save the expanded archive, choose the folder

in which Microsoft Excel 5.0 was installed (usually named "Microsoft  Excel"). 4. Change the file name of your existing "Microsoft Excel" to "Old Excel."

5. The replacement file will be named either; "Excel for 68K", "Excel for

PPC" or "Excel for 68K and PPC". Rename this file "Microsoft Excel" and  restart your Mac. To verify that the fix was installed correctly, boot Microsoft Excel and enter 1.40737488355328. If the number maintains the correct value upon entry, the fix has been successfully installed. You may now remove "Old Excel" from your system. If the number is not correct, please verify that you have completed the installation instructions above correctly. Make sure you have obtained the replacement executable file for your machine. If you are still unable to verify the fix, please contact Microsoft Technical Support at the number provided below.

Thank you again for using Microsoft Excel. We hope these problems have not inconvenienced you. Reference the FAQ below to answer any questions you might have about the fix. If you have further questions, please contact Microsoft Technical Support at (425) 635-7080.

Frequently Asked Questions for Macintosh

1. Q. I heard there is a problem with Microsoft Excel changing the values of some specific numbers, what's the situation? A. In Microsoft Excel there is an error that will cause three specific

sequences of fifteen digits to change their value either when entered as  an individual entry or when derived from specific functions.

2. Q. Can you tell me what that means in more common terminology? A. What this means is that if you have entered one of three specific

fifteen digit numbers or come to this number as the result of a formula, Microsoft Excel might have changed the value of the number.

3. Q. What are the chances that I have been affected? A. Although it is hard to have an exact number, we believe this will only

affect a very small number of customers. In fact, based on our internal analysis the likelihood of any one of these sequence of digits appearing in a customer's spreadsheet is approximately 1 in 5 billion. Remember, the only way that this will affect you is if you have these three specific combinations of fifteen digits.

4. Q. If there is such a small likelihood of this occurring, why worry about fixing it? A. Our customers depend on Microsoft Excel to compute their numbers

accurately and we want them to feel confident when using the product. Even though the probability of one of our customers having a problem with this is low, we can't judge the probability for each and every customer. So, we are trying to get all of the facts regarding this out so that you can determine for yourself if you need the fix. The solution will be available to all customers that own Microsoft Excel or Microsoft Office. This fix is available at no charge.

5. Q. What are you doing to fix this? A. We have created a solution that will correct this error. The fix is

currently available free of charge.

6. Q. So, what are the numbers that cause this error? A. The specific sequences of digits are: 140737488355328, 281474976710656

and 562949953421312. The decimal point may be in different places. In  addition if you are dealing with calculations, the result has to be one of these three sequences of digits, plus or minus a number less than approximately one-half of the next decimal, times a power of 10. And this is only a problem when you refer to the result in certain functions, namely: int, ceil, floor, roundup, and if.

7. Q. Why these specific numbers? A. The common bond between these numbers is that they happen to be 2 to the

47th, 48th, and 49th power, respectively.

8. Q. Does this mean I have to check to make sure any 15 digit numbers in     my files have not been changed by Microsoft Excel? A. No. Unless you entered in one of the three specific sequence of digits

mentioned above or have utilized one of the specific formulas mentioned above with very long numbers you should be fine. To double check; however, all you have to do once you have installed the patch is to open a file and press Command+Shift+F9, by doing this the patch will correct any numbers that were derived from functions incorrectly.

9. Q. What versions of Microsoft Excel for Macintosh does this affect? A. We have found this in versions of the product dating back to Microsoft

Excel 3.0 for Macintosh. Other Macintosh versions of the product affected include Microsoft Excel 4.0 for Macintosh and Microsoft Excel 5.0 for Macintosh. We will make the fix available for no charge for any of our customers using any of these versions of Microsoft Excel.

10. Q. How do I get the fix? A. To receive the fix for Microsoft Excel for Macintosh, call Microsoft at

(425) 635-7080. The fix was made available in April and is provided at no  charge.

11. Q. As a network administrator, how do I install the fix? A. Decompress the fixed Microsoft Excel application file and place it on

the network. Users can then copy the application to their local machines, replacing their previous version of the Excel application.

12. Q. How did you find out about this? A. One of our customers actually found it when working with a formula that

derived the number 1.40737488355328. This customer's work required that he create a formula in Microsoft Excel which explicitly calculated 2 to  the 47th and take the integer portion of it. We were not previously aware of this error and are grateful that it was brought to our attention. Additional query words: 5.00 5.00a

Keywords         : xlmac Version          : MACINTOSH:5.0,5.0a Platform         : MACINTOSH