Almost every time I use netinstall, I see this problem.

The router appears in the selection window, I select it, I select the packages or the predefined group I want, and I click on the Install button. Instead of netinstall doing the installation, it just reports, "Selected N package(s)." It never installs -- it just repeats the same advisory until I quit out of netinstall and re-launch it, whereupon the router appears in the window again, i select it, I leave the selection set to "Previous install" (which at that point represents what I was trying to install before I quit), and at this point, the Install button will perform the installation just fine.

A related behavior is that maybe a third of the time I use netinstall this happens even if I don't select packages (leaving the default set to "Previous install"). I get the advisory message until I quit and relaunch, at which point netinstall starts installing things again.

I'm not sure whether the behavior is related to changing the packages, or the time it takes to change the packages (rather than just slapping the install button very soon after launching).

It's not a critical bug, but it's a pain, and if I'm not the only one seeing it, I'll report it formally to support.

Ensure that you have the recent Netinstall and the recent RouterOS

Yes, I've tried keeping netinstall up to date. The latest version always fails just like the others.

Keeping ROS up to date is meaningless, since the whole point of netinstall is that it should work even when ROS is damaged or absent.

What kinda routerboard is it?

Every model that comes through here. 911s, SXTs, 912s, mAPs, hAP lites, old 711s. Yesterday it happened to me on an LHG.

Try a different PC. And use Windows and not Linux.

Also disable any firewalls on the PC for the time being.

Don't have another PC, don't use Linux (not sure where you got that impression), and a firewall wouldn't interfere with one launch of a program but not another. Thanks for responding.