These are stock ISA rules (HTTP Filter) on a Small Business Server 2003 Premium R2. So anyone with the same environment will run into this problem. The HTTP filter can either be on or off with no other options. I'd rather have it on.

This should be an easy fix.

Looking at the source in Login.ascx.vb, I find:

        Private Sub cmdPassword_Click(ByVal sender As System.Object, ByVal e As EventArgs) Handles cmdPassword.Click
            Dim ReturnUrl As String = NavigateURL()
            If Not String.IsNullOrEmpty(Request.QueryString("returnurl")) Then
                ReturnUrl = Request.QueryString("returnurl")
            End If
            ReturnUrl = HttpUtility.UrlEncode(Request.RawUrl)

            Response.Redirect(NavigateURL("SendPassword", "returnurl=" + ReturnUrl), True)
        End Sub
 

In the above code block, the first two statements assigning a value to ReturnUrl are useless as ReturnUrl will be overwritten in the following step. That looks like either a coding error (using RawUrl) or bad housekeeping by not deleting useless code. Either way, it needs to be looked at.

        Private Sub cmdRegister_Click(ByVal sender As Object, ByVal e As EventArgs) Handles cmdRegister.Click
            If PortalSettings.UserRegistration <> PortalRegistrationType.NoRegistration Then
                Dim ReturnUrl As String = NavigateURL()
                If Not String.IsNullOrEmpty(Request.QueryString("returnurl")) Then
                    ReturnUrl = Request.QueryString("returnurl")
                End If
                ReturnUrl = HttpUtility.UrlEncode(ReturnUrl)

                If PortalSettings.UserRegistration = PortalRegistrationType.PublicRegistration Then
                    'Pass return url to register
                    Response.Redirect(RegisterURL(HttpUtility.UrlEncode(ReturnUrl), Null.NullString), True)
                ElseIf PortalSettings.UserRegistration = PortalRegistrationType.VerifiedRegistration Then
                    'Pass return url to register as original url  and return to this control to login after regsitration
                    Response.Redirect(RegisterURL(HttpUtility.UrlEncode(Request.RawUrl), Null.NullString), True)
                End If
            End If
        End Sub
 

In this event handler, UrlEncode can be called twice on the same URL. Removing the second call to UrlEncode would avoid that and improve efficiency by eliminating a redundant call. Like so:

        Private Sub cmdRegister_Click(ByVal sender As Object, ByVal e As EventArgs) Handles cmdRegister.Click
            If PortalSettings.UserRegistration <> PortalRegistrationType.NoRegistration Then
                Dim ReturnUrl As String = NavigateURL()
                If Not String.IsNullOrEmpty(Request.QueryString("returnurl")) Then
                    ReturnUrl = Request.QueryString("returnurl")
                End If
                ReturnUrl = HttpUtility.UrlEncode(ReturnUrl)

                If PortalSettings.UserRegistration = PortalRegistrationType.PublicRegistration Then
                    'Pass return url to register
                    Response.Redirect(RegisterURL(ReturnUrl, Null.NullString), True)
                ElseIf PortalSettings.UserRegistration = PortalRegistrationType.VerifiedRegistration Then
                    'Pass return url to register as original url  and return to this control to login after regsitration
                    Response.Redirect(RegisterURL(HttpUtility.UrlEncode(Request.RawUrl), Null.NullString), True)
                End If
            End If
        End Sub
 

IMHO, these are coding errors and easy to fix, so I can't see why they wouldn't be fixed.

Charles just pressed the checked in button :).

if it is checked in it will be including in upcomming DNN 5.2.1