Sounds like you're not putting your phone in download.. Below is taken directly from the OP of that thread..
read, read, read.. and don't do like some and say it's too verbose..
Oh, and place the phone in download while you're NOT
connected to your pc.. (That's also in to OP..)
Originally Posted by sfhub
5) Place phone in ODIN download mode
Power down phone
Wait for capacitative button lights to turn off
Simultaneously Press and Hold [Power] [VolDn] until confirmation screen appears
Press [VolUp] to enter Download mode