Restrict Data Entry in a cell if the preceding cell is not filled

[TJ7009]

Hi

I want to restrict data entry in to a cell if the preceding cell is not filled. i.e, data entry to 2nd cell will be possible only if the first cell is filled up. Can somebody help me out.

Thanks,
TJ

[Special-K]

Assuming data cannot be entered into A2 unless A1 has been entered.

Data / Data validation

Untick "Allow blanks"

Formula
=LEN(A1)<>0