The web application at [URL] could not be found.

Question

Hi,
I am trying to run a simple code like finding all the users in the SharePoint site.
But I am seeing this error constantly no matter what I do!!
The Web application at [https://xxxxxx] could not be found. Verify that you have typed the URL correctly. If the URL should be serving existing content, the system administrator may need to add a new request URL mapping to the intended application.
I've looked into all the answers on the forums but still stuck with this error.
I am a beginner in SharePoint, and I am really not sure about the AAM and IIS settings that needs to be set inorder to get rid of this error.
If someone could point me in right direction that targets beginners that would be really helpful.
Also, I noticed that my IIS is blank on the dev server that I am working on with Visual Studio and SharePoint installed on it. 
Is this something that is causing this error?
Thanks

Answer 1

Note: you need to enter the SharePoint site URL 
To authenticate:
f you are connecting to office 365 then use the following code:
using (srcContext = new ClientContext(txtUrlFrom.Text))
SecureString passWord = new SecureString();
foreach (char c in txtPasswordFrom.Text.ToCharArray()) passWord.AppendChar(c);
srcContext.Credentials = new SharePointOnlineCredentials(txtUserNameFrom.Text, passWord);
if you are using on premise SharePoint 2013 use this code:
using (srcContext = new ClientContext(txtUrlFrom.Text))
NetworkCredential credentials = new NetworkCredential(txtUserNameFrom.Text, txtPasswordFrom.Text);
Example to retrieve data:
Web srcWeb = srcContext.Web;
List srcList = srcWeb.Lists.GetByTitle(srcLibrary);
ListItemCollection col = srcList.GetItems(new CamlQuery());
srcContext.Load(srcList.RootFolder);
srcContext.Load(srcList.RootFolder.Folders);
srcContext.Load(col);
srcContext.ExecuteQuery();
to retrieve users:
Private void GetData(object obj)
MyArgs args = obj as MyArgs;
try
if (args == null)
return; // called without parameters or invalid type
using (ClientContext clientContext = new ClientContext(args.URL))
// clientContext.AuthenticationMode = ClientAuthenticationMode.;
NetworkCredential credentials = new NetworkCredential(args.UserName, args.Password, args.Domain);
clientContext.Credentials = credentials;
RoleAssignmentCollection roles = clientContext.Web.RoleAssignments;
ListViewItem lvi;
ListViewItem.ListViewSubItem lvsi;
ListViewItem lvigroup;
ListViewItem.ListViewSubItem lvsigroup;
clientContext.Load(roles);
clientContext.ExecuteQuery();
foreach (RoleAssignment orole in roles)
clientContext.Load(orole.Member);
clientContext.ExecuteQuery();
//name
//MessageBox.Show(orole.Member.LoginName);
lvi = new ListViewItem();
lvi.Text = orole.Member.LoginName;
lvsi = new ListViewItem.ListViewSubItem();
lvsi.Text = orole.Member.PrincipalType.ToString();
lvi.SubItems.Add(lvsi);
//get the type group or user
// MessageBox.Show(orole.Member.PrincipalType.ToString());
if (orole.Member.PrincipalType.ToString() == "SharePointGroup")
lvigroup = new ListViewItem();
lvigroup.Text = orole.Member.LoginName;
// args.GroupsList.Items.Add(lvigroup);
DoUpdate1(lvigroup);
Group group = clientContext.Web.SiteGroups.GetById(orole.Member.Id);
UserCollection collUser = group.Users;
clientContext.Load(collUser);
clientContext.ExecuteQuery();
foreach (User oUser in collUser)
lvigroup = new ListViewItem();
lvigroup.Text = "";
lvsigroup = new ListViewItem.ListViewSubItem();
lvsigroup.Text = oUser.LoginName;
lvigroup.SubItems.Add(lvsigroup);
//args.GroupsList.Items.Add(lvigroup);
DoUpdate1(lvigroup);
// MessageBox.Show(oUser.LoginName);
RoleDefinitionBindingCollection roleDefsbindings = null;
roleDefsbindings = orole.RoleDefinitionBindings;
clientContext.Load(roleDefsbindings);
clientContext.ExecuteQuery();
//permission level
lvsi = new ListViewItem.ListViewSubItem();
string permissionsstr = string.Empty;
for (int i = 0; i < roleDefsbindings.Count; i++)
if (i == roleDefsbindings.Count - 1)
permissionsstr = permissionsstr += roleDefsbindings[i].Name;
else
permissionsstr = permissionsstr += roleDefsbindings[i].Name + ", ";
lvsi.Text = permissionsstr;
lvi.SubItems.Add(lvsi);
// args.PermissionsList.Items.Add(lvi);
DoUpdate2(lvi);
catch (Exception ex)
MessageBox.Show(ex.Message);
finally
DoUpdate3();
Kind Regards, John Naguib Technical Consultant/Architect MCITP, MCPD, MCTS, MCT, TOGAF 9 Foundation