If I have an array of data in cells A1:A10 where some are blank, say the data is a,b,c,d,e,f with the rest of the cells blank. Say I place a validation on cell A11 using a list of A1:A10 and select ignore blanks, why is it that when I then add a letter, say h to one of the empty cell, the validation no longer ignores the blanks? It also happens when I clear one of the existing cells? Can I stop this from happening?

I want to be able to add and remove data from a list while having a validation on but ignore the blanks. Any help would be appreciated. Thanks