a Formula that might involve ISBLANK, AND, or OR

[IanCPL]

[TABLE="class: grid, width: 500"]
<tbody>[TR]
[TD][/TD]
[TD]XX
[/TD]
[TD]XY
[/TD]
[TD]XZ
[/TD]
[/TR]
[TR]
[TD][/TD]
[TD]AA
[/TD]
[TD]BB
[/TD]
[TD]CC
[/TD]
[/TR]
[TR]
[TD][/TD]
[TD](Formula)
[/TD]
[TD](Formula)
[/TD]
[TD](Formula)
[/TD]
[/TR]
</tbody>[/TABLE]

What i am trying to do is if 2/3 are Blank between XX, XY and XZ then give error. But if all are blank or all have a value in it then do nothing

 

[dreid1011]

Perhaps this:

=IF(OR(COUNTA(XX2:XZ2)=3,COUNTA(XX2:XZ2)=0),"","ERROR")