Alejandro,
CCing I assume you read my reply, if not read it.
Cetin

>Thanks. That works fine until they save the file and open it again (as they would if they need to make a correction).
>
>We may be stuck here. Maybe we can allow them to add a character not in any key (such as ":") as the first char if key has leading zeroes and then ignore it or a trailing alpha char beyond the 6 chars that form the key.
>
>Thanks.
>
>>They should not "format" the numeric data in the column, but make a number stored as a text:
>>
>>'000102
>>
>>Quotation mark first!
>>
>>
>>>A customer provides some information to our app in CSV files which they prepare using Excel. One of the columns has a key value which is a 6 char string. Some clients have defined keys with all digits such as "000102". If they format the column in Excel as text the file is saved with the full key, but if they happen to open the file again with Excel the value is interpreted as numeric and the leading zeros are lost.
>>>
>>>Is there any solution to this?
>>>
>>>TIA,
>>>
>>>Alex