Use a script for a telnet session

I have a problem with my script. It seems my password is wrong. #!/usr/bin/expect set ip [lindex $argv 0] spawn telnet $ip set timeout 10 expect "Login:" send "administrator\r" expect "Password:" send "123456" send "\r" It says, login incorrect. But it works, when i use cmd on Windows to telnet to my phone, it works with "administrator" and 123456 as password. I don't know why in my script, I could not log on successfully. I have to use this script to downgrade/upgrade my phones.