backup a program from beckhoff "cx9001-1101"

Dear All,
I've tried to get a backup copy from our CX9001-1101 PLC by using TwinCAT 3, and I followed the instructions on how to connect the PLC
But unfortunately, as I reached the step of "open project from target", a pop-up message has been displayed "could not retrieve version info from project of selected target<local>, load default version?"
I said "ok" but no response at all.
My system is windows 10, 64-bit, x64
My setup software are, visual studio isolated and integrated and TwinCat 3 Engineering.
Kindly, I need support, guys, to have this a backup copy, what should i do?
Thanks all.

Are you sure the version of TwinCAT 3 you are using is the same as what was used to load the project into the PLC originally?

No sir, I'm not sure