Defaulting to date format

[Lea from CA]

Up until a few weeks ago all was well with Excel07. Then it started to
change the default number format to a date format. When I import a file to
excel or do a copy paste, excel automatically formats numbers as dates.
Suggestion was to create a template and save in xlstart but then everything
will be formated as general. why did excel stop automatically detecting
number formats? how can I change the default settings?

 

[KLHills]

I have the same problem. I have a large file (~2.5 MB) that has several
different types of formatting and some cells that are still in default
formatting as "general." Recently, the cells formatted as "general" changed
to a "date" format. I checked empty cells and they have the default "date"
format, too. When I first noticed this issue, I had an older version
restored from a backup. Yesterday, it happened again and I asked for another
old version to be restored from backup. The new backup version has default
set to "date" AND the older version that I had restored a few weeks ago also
now has the default set to date.

I, too, want to know how to fix this file because recreating it or finding
all the cells formatted to default will be extremely time consuming.
I am working in Excel 2007 and the file has been converted to 2007 (although
it was probably originally created in a version of excel even before
95-2003).

Lea from CA-- I'm sorry not to be able to answer your issue, but you are not
alone...

 

[Samir Mehta]

I have similar issue with my Excel 2007. Most of my general formatted cells
change to date format automatically. I have to go back and change all of them
and it will work fine for sometime then go back to date format. It seems that
excel 2007 has a bug in it.

 

[KLHills]

What I also find really odd is how a new workbook opens with general format
but a new tab inserted into the corrupted file has the default date format.
And it must be a bug in Excel, otherwise we wouldn't all have the same
default from general to Date formatting.

Lea & Samir: What else do our files have in common:
1. Are they fairly large files?
2. Does this bug occur on other large files?
3. Was the file converted from 2003?
4. Is it a file that is updated periodically with new versions created?
5. Does more than one person save changes to the file?
6. Do you import data from spreadsheets prepared by others?
7. Do you import data from an ERP?
8. Are there more than 25 tabs in your files?
9. Does each of the tabs have a multitude of different types of formats and
layouts?
10. Do you use color coding in the workbook?
11. Do you use conditional formatting?

If the bug only occurs on a few of your files and you can think of other
things that may be different with those files from other files, please add
them to my list of questions.
Here are my answers to the questions above:
1. Yes, but I have other files that are much larger that don't have this issue
2. Not that I've noticed
3. yes
4. yes
5. yes
6. yes
7. yes (from JDEdwards)
8. yes, about 50 tabs
9. yes, different fonts, formats, conditional formatting, etc.
10. yes, tabs and cells are color coded. Conditional formatting also adds
color
11. yes.

 

[KLHills]

I FIGURED IT OUT!!! (with minimal help from MSFT)

1. If a new workbook has the proper default. Open both a new workbook and
open the workbook with the wrong default format. Otherwise, make the new
workbook have the proper default format.
2. On the Home menu, go to the Styles block and select the drop down menu
of Cell Styles.
3. At the bottom, select the item Merge Styles.
4. Select the new workbook with the proper default style.
5. click on Okay. It will ask you "Merge styles that have the same names?"
so if you have other styles, it will probably overwrite those.

Good luck!