How do I fix a YMD format?

[Frustrated]

An Excel file sent to me used a YMD date format.
Since then, all my old and new Excel files default to the YMD format.
Selecting a cell, a cell range, or a column, and then
Data>Text to Columns>Next>Next>General/Text/Date = MDY (or any other date
format selection) >Finish has *no*effect. No changes are made to the file,
and going back to Data>Text to Columns... shows the data format to still be
YMD!

Format>Cells>Date & choose any format has no effect either.

Did I get an infection from the worksheet that was sent to me?

How can I get back to the MDY date format?

I need a generalized solution since I have many worksheets in each of
several workbooks that are affected.

 

[Pete_UK]

Perhaps they are text values that just happen to look like dates in
yyyymmdd format, in which case formatting will have no effect on them.

Pete

 

[Fred Smith]

First, check your regional settings (in Windows). Did the date format
accidentally get set to YMD? This could be the reason all your old files are
defaulting to YMD.

Second, when you do Text to Columns, you need to select YMD as the date
format so that Excel will convert the text to a date. So the command
sequence should be Data>Text to Columns>Next>Next>Date>YMD>Finish. Now you
should be able to reformat the dates. Choose a date format without an
asterisk to ensure that your Windows regional settings aren't affecting the
format.

Regards,
Fred