Assuming that you are working with DotNetNuke 5x, the call to obtain the current UserInfo object would not be Membership.GetUser() but rather:

Dim currentUser As DotNetNuke.Entities.Users.UserInfo
currentUser = DotNetNuke.Entities.Users.UserController.GetCurrentUserInfo()

I would then test that a non-null UserInfo object would be returned before accessing the Email property:

Dim currentUserEmail as String

If currentUser Is Nothing OrElse currentUser.UserID = -1 Then
    currentUserEmail = String.Empty
Else
    currentUserEmail = currentUser.Email
End If

However, as I recall for a valid DotNetNuke context t to be available in a .aspx page, the page should inherit from DotNetNuke.Framework.PageBase and not from System.Web.UI.PageBase.

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Bill, WESNet Designs
Team Lead - DotNetNuke Gallery Module Project (Not Actively Being Developed)
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