I have Created an Item Type as Popup LOV, It will open LOV.I have added a validation like item not null , having some value ,click on Apply button. Once close the popup then again will open then particular field show the validation message. I have written Clear process but it will clear the value but the message on the item field.
Vinish Kapoor
Check your Apply button property Execute Validations. If it is turned off then turn it on.