remedy工作室:asp.net下,用户注册,验证该用户名是否存在,出现问题

现在是Then处发生语法错误
编译器错误信息: BC30035: 语法错误。

源错误:
行 65： If dr.hasRows()
行 66： Response.Redirect("register.aspx")
行 67： Then

c:\inetpub\wwwroot\register.aspx(67) : error BC30035: 语法错误。

Then
~~~~
//下面是代码
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.OleDb" %>
<script language="VB" runat="server">
Dim conn As OleDbConnection
Sub Enter_Click(Sender As Object, E As EventArgs)
'建立Connection对象
conn=New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & Server.Mappath("admin/wwwlink.mdb")) '建立Connection对象
'建立Command对象
Dim sql,strA,strB,strSql As String

sql="select U_name from register where U_name='" & U_name.text & "'"
Dim cm As New OleDbCommand(sql, conn)
Dim dr As OleDbDataReader=cm.ExecuteReader()
If dr.hasRows()
Response.Redirect("register.aspx")
Then //此处发生语法错误

strA="Insert Into register(U_name,U_password,P_phone,Fax,Email,submit_date"
strB=" Values('" & U_name.text & "','" & U_password.text & "','"& P_phone.text &"','"& Fax.text &"','"& Email.text &"',#" & Now() & "#"
If Trim(topic.Text)<>"" Then '如果传真不为空，就执行
strA=strA & ",topic"
strB=strB & ",'" & topic.Text & "'"
End If
strSql=strA & ")" & strB & ")"
Dim cmd As New OleDbCommand(strSql, conn)
Dim Exp As Exception
Try
'执行操作，插入记录
conn.open()
cmd.ExecuteNonQuery()
conn.close()
Response.Redirect("registerok.aspx") '正常添加后，返回首页
'Catch Exp
'message.Text="发生错误，没有正常插入记录"
Catch ex As Exception
Throw New Exception(ex.ToString())
End Try
End If
End Sub
</script>