s ftp=##class(%Net.FtpSession).%New()
 s ok=ftp.Connect(server,user,password,port)
 s ftp.Timeout = 100
 
 i ok {
   
   s ok=ftp.SetDirectory(directory) 
   i ok {
     n files,file
     
     s ok=ftp.NameList(directory,.files)
     i ok {
       f i=1:1:files.Count() {
         s file=files.GetAt(i)
         i (ftp.SetDirectory(file)) {
           d ftp.SetToParentDirectory()
           continue
         }
         s fname=$p(file,"/",$l(file,"/"))
         s ok=ftp.Retrieve(file,.data)

There is test folder inside my sftp server. I executed the below lines of code

s ssh = ##class(%Net.SSH.Session).%New()

d ssh.Connect("host")

d ssh.AuthenticateWithUsername(username,password)

d ssh.OpenSFTP(.sftp)

s remote="\test\sample1.txt"

s local="c:\orders\sample1.txt"

s status=sftp.Put(local,remote)

I get the below error 

"MSSH Error [8010102B]: Unable to send FXP_OPEN* [8010102b] at SFTP.cpp:539,0Put,IM%e^zPut+2^%Net.SSH.SFTP.1^1e^^^0"