Excel data validation error

[Rick]

Data validation setting a minimum text string length does not work. I even
clear the 'Ignore Blank' check box. If I edit the text string in the formula
bar, then I data validation works and I am unable to backspace or delete the
string in the cell.

However, if I just hit the DELETE key, then the cell is emptied, and data
validation does not complain about the null string left in the cell.

Is there any way to require a cell to be filled in?

Thanx.