Hi @undefined
I do not think the problem here is the activation process, you have already done it or your reader does it automatically, if you have not started this you could not send the select file command and get an 9000, the thing here is that you are trying to talk to the "folder" where the files are stored, after selecting that you can select the file inside of it. you can see that process in the script I sent first I select D276000085010100 by DF name then I select E104 by FID


after selecting the file, then you are selecting something where you can read or write information, be carefull what file are you modifying, I recommend checking each file in the DS before adding information on them.
please try this and let me know.
Have a great day!
BR
Jonathan