Update DP 750 from firmware


I just bought 3 DP750 devices and they came with very old firmware.
I need to update them. They have firmware and I want to update them to the latest version.
I have to update 1st with firmware, then with, then, then and the current
The last 3 I got them.
Does anyone know where I can get the previous ones?




No, you can upgrade to 9.1 directly.
If they not configured then factory unit after this to be sure that everything is ok (it is not needed as usally there is no problem at all).


Thank you very much for the help. I did not dare to do it directly. I already got the previous firmware. Greetings. Daniel