Reject any entry if x cell is blank

[drgkt]

Hi
I want A2 to reject any entries if A1 is blank.
So, in A2 Data Validation - Custom I TRIED
=IF(ISBLANK(A1),"",)
or
=IF(A1="","",)

Both did not work.

Any ideas?

[CK76]

=$A$1<>""

And also uncheck "Ignore blanks".

For usability, remember to set "Input Message" and "Error Alert".

[drgkt]

That does not work either

[CK76]

See attached sample.

Note that without VBA, it will not remove value if A1's value is deleted (it will give warning if you modify value in A2).

[garrycarton]

That does not work either

How this will work? I am interested to learn.

[Kamal Asharaf]

Dear CK76,
May we request you to explain as how it has been done. This facility may be used in different versions.

Kamal Asharaf.

[CK76]

Hmm? It's done exactly as it was explained in post#2