We've tried our own app on iOS 11, but we had no problem to connect to iMZ320 running V73.20.01Z firmware. For your case, it's unclear whether it is an issue of your app with iOS 11 or not. If you don't mind, could you create a test app to reproduce the problem and share the test app with us. We'd like to drill it down to see if it's an issue with our printer's firmware or not.
Thank you in advance.
Iam usinging adobe flex for that
So I have created an ANE to do the printing ,and this is now a problem so for now if u can just send me a link to the firmware v.7.19 so that I can let my customers work then I will find a solution for that