I think this code will help you.
private const string DropBoxUsername = "abc@hotmail.com";
private const string DropBoxPassword = "password";
private const string FolderName = "MainFolder";
private const string UserEmail = "abc@hotmail.com";
protected void BtnUploadClick(object sender, EventArgs e)
{
var client = new SkyDriveServiceClient();
// log on into drop box using username and password
client.LogOn(DropBoxUsername, DropBoxPassword);
// verifying the company folder is available or not
WebFolderInfo userskyDrivefolder = null;
WebFolderInfo clientskyDrivefolder =
client.ListRootWebFolders().FirstOrDefault(subWebFolder => subWebFolder.Name == FolderName);
if (clientskyDrivefolder != null)
{
foreach (WebFolderInfo subWebFolder in client.ListSubWebFolders(clientskyDrivefolder))
{
if (subWebFolder.Name == UserEmail)
{
userskyDrivefolder = subWebFolder;
break;
}
}
}
}