imap.SelectFolder("inbox/folder_to_select");
var imap = new Imap();
imap.Connect("test.rebex.net", Imap.DefaultImplicitSslPort, SslMode.Implicit);
imap.Login("demo", "password");
ImapFolderCollection folders = imap.GetFolderList("", ImapFolderListMode.All, true);
foreach (ImapFolder folder in folders)
{
Console.WriteLine(folder.Name);
}