downloading webpage error

:wave:

I've asked this question once before the help i got last time didnt work out

Dim hi as string = string.join("|", Form2.RichTextBox1.Lines)
what this does is it combines everything and put it into one string example: hi|bye|sky
the url would= www.example.com/user/hi|sky|bye

so im asking again

what im trying to achieve is to download webpage source of each profile in richtextbox1.lines tried 3 different ways

#1
Try
Dim client As New System.Net.WebClient
Dim source As String = client.DownloadString("http://www.youtube.com/user/AmazingLife247")
RichTextBox1.Text = source
Catch

End Try
---WORKS PERFECTLY AND IS WHAT IM TRYING TO DO EXCEPT WITH NOT A SINGLE PROFILE

#2
Try
Dim client As New System.Net.WebClient
Dim source As String = client.DownloadString("http://www.youtube.com/user/" & RichTextBox1.text.ToString)
RichTextBox1.Text = source
Catch

End Try
---TRIED .TEXT FOR A TEST NOT SURE HOW THIS HAPPENS BUT IT PROMPTS ME TO THE LOGIN PAGE AND DOESNT DOWNLOAD THE PROFILE SOURCE

#3
Try
Dim client As New System.Net.WebClient
Dim source As String = client.DownloadString("http://www.youtube.com/user/" & RichTextBox1.Lines.ToString)
RichTextBox1.Text = source
Catch

End Try
---THIS IS WHAT IM TRYING TO DO BUT IT DOES NOT DO ANYTHING NOT EVEN GET THE SOURCE OF THE FIRST WORD IN RICHTEXTBOX1