Thanks everyone for the input. Will look into them all.

>Greetings all,
>
>I am running a validation code that checks user name text box value to see if it matches their double-entry value. The text boxes are on Page 1 of 3 pageframe. Screen syntax goes as:
Thanks everyone for the input. Will look into them all.

>
>Step 2. Enter your User Name , step 2a. Re-enter your user name
>
>The Validation button sits on page 3 of the pageframe. Here's the validation code:
>Do Case
> CASE ALLTRIM(This.parent.parent.Page1.txt_UserName1.Value) NOT EQUAL TO ALLTRIM(This.parent.parent.Page1.txt_UserName2.Value)
>...notify user that the entries do not match
> EndCase
>
>Testing scenario: When I enter a user name is UserName1 text box, and leave Username2 textbox empty, the validation code DOES NOT fire off. I have tried use both NOT EQUAL TO operator(s)
>
>Any ideas ?

Required reading: https://www.vfphelp.com/vfp9/_5wn12pc59.htm