how to Upload/Download from a HTTPS server through C#

Question

I have read your article on connecting and downloading a file from HTTP and Proxy server through C#.NET. Currently i am working on an application that would upload and download files from a HTTPS server, without any proxy server between. but i cannot get through it. Somewhat using your code in the above article i get the message in the resultant string that "Virtual user logged in". I am kind of stuck in this scenario.
Could you kindly help me out of it.

Nauman Farooq · Answer

can you suggest me some free https server from where i can check my code. i think there are some restrictions on my side by network dept.

Bechir Bejaoui · Answer

Your code seems to be perfect! Are you sure that your ID and Password are corrects or even they are correct they have to be valid Could you try to access from a computer to which you have never previously identified? but change the userID and the password try this i said that because I have a doubt about the surrounding systems whether they have been configured to disallow certain patterns of HTTP traffic.

Nauman Farooq · Answer

Dim fullfiledownload As String Dim filefullpath As String Dim fileurl As String = HTTPS url Dim filedownload As String = filename Dim newfilename As String = saved filename Dim filepath As String = D:\ Dim userid As String = userid Dim userpassword As String = password fullfiledownload = fileurl & filedownload filefullpath = filepath & newfilename ServicePointManager.CertificatePolicy = New Certpolicy() //returning true for all certificates. Dim wc As New WebClient Dim myCredentials As New NetworkCredential(userid userpassword) wc.Credentials = myCredentials wc.DownloadFile(fullfiledownload filefullpath) this code is giving me error  The remote server returned an error: (401) Unauthorized . I dont know why. I am using Serv-U for making an HTTPS server. and connecting to it.

Bechir Bejaoui · Answer

Sorry to pose another question but I try to understand so I can answer correctly Is it the unzipped file the endomaged or the zip file it self?

Nauman Farooq · Answer

it is a zip file.

Bechir Bejaoui · Answer

what is the nature of the downloaded file I mean the extention

Nauman Farooq · Answer

I have added a certificate policy ...but now the application does not give an error but an incorrect file of 31 bytes every time... On a close look reveals that the repose i get after my download statement is Virtual User logged in and every time i get this error. I have allowed all certificates in my certificate policy.

Bechir Bejaoui · Answer

Then you miss to implement a Certificate Policy

Nauman Farooq · Answer

When downloading the file from your code. i get the following exception The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel.. I have given the credentials also but got no sucess.

Bechir Bejaoui · Answer

WebClient client = new WebClient(); client.UploadFile(yourAdressPUTyourfilepath); oClient.DownloadFile(yourAdress yourFilepath);