What is the problem? Please help.

I used RequiredFieldValidator to control my textbox in order the user entered the information to textbox-
I put controlToValidate equal to text1
And errorMessage  *
On button click I wrout
if (!Page.IsValid) return;
Label1.Text = Text1.Text;

But the brouser sais that 
?????? ??????? ? ?????????? '/'. ? WebForms ??? ?????? UnobtrusiveValid ...