The * and ? are wildcard characters in Excel, and you can use them to
replace characters if the data validation list refers to a worksheet
range. For example, if your data validation dropdown is a list of month
abbreviations:
Jan
Feb
Mar, etc.

you could enter J* or J?n as accepted values.

To limit the entries to exact matches to the list, you could type the
list in the data validation dialog box, instead of using a worksheet
list as the source.

Loligo wrote:
In Excel 2007 (Windows XP Pro), I created a dropdown list (on another
worksheet in the same file) of valid characters with which names can be
created. The list includes all the characters on the standard keyboard,
except for spaces and * \ ? < : ' " | I have left the "ignore blanks"
unchecked. The system successfully prevents all of the forbidden characters
from being used, except for the *. The only way I can keep the * from being
allowed is to completely depopulate the list of allowed characters. Why?


--
Debra Dalgleish
Contextures
http://www.contextures.com/tiptech.html