Pete wrote:

If you are saying that the cell contains a formula which brings a value
from somewhere else, then it doesn't matter - the format of this cell
can be set independently of the other cell(s). Try it, and see if it
does what you want.

If there is a formula in the cell you are trying to format, then the
formula could be modified to give you the effect you are wanting -
please post it here.

It's just something like that : =TEXT(A1;"00###")
For blank cells, I get "00", but I would want the cells to remain blank...