file in nrf tools isn't selectable

[Agoff]

why is zip for dfu in nrf Toolbox not  selectable use latest  1.6.1 version , this happen after update  the previous  version has worked good.

[Agoff]

I've tried to remove and reinstall it couple of times but got same result. Do I need to change options, I've red some advise like  change file explorer ?