How can I add any alpha numeric with or without leading zeros to a cell without getting an excel warning?

In a cell, how can you have any number or letter for a given cell without getting an excel warning. I tried converting to text but that seems to have little or no affect. I'm trying to use the x:num or x:str

examples:

0000005123
ABCDEFGHIJ
1111111110
0111111111
111111111
9a
开发者_开发技巧9

I want the cell to have any combination and not get the little green arrow warning.

if you store a number as text in order to maintain leading zeroes, it will always give you a warning unless:

1) you disable the "Numbers formatted as text" proofing option

2) if you need leading zeroes, you can custom format the cells as 00000000 or whatever number of zeroes you need. then you will store numbers as numbers and alphanumeric entries will be stored as text without the warning.

3) you can also enter them like this: let's say you want to enter 000123, you can enter it as ="000123" and it won't give you a warning