Please see my screenshots to go with this attempt to describe what's going on:
I have followed the Instructions, networking is setup correctly and router shows up as expected.
However cannot select RouterOS package.
Says 1-package found in directory but cannot view or select it.
Can select folder but shows then blank "loaded 0 packages".
There is certainly the routeros npk file in that folder I am trying to load.

If I restart netinstall It then shows the package selected but install button is grayed out and key is not shown or visible.
If I click on the displayed router it then shows the existing key but package selected disappears, is blank and shows "loaded 0 packages" again and unable to select install.
And attempts to browse to the package location does the same problem as above, and does not show up.
I have tried every combination of restarting netinstall and booting up the Mikrotik in netinstall mode while netinstall is running or not running.
Same result.
I am confused.
Just starting netinstall (with Mikrotik router already up & running in netinstall mode) router shows up and shows package "routeros 7.14.2 Main package with most of services and drivers"
As selected and about to be installed but router key field and install button are blank/not available (grayed out)"
If I click on the router that is shown they existing key appears and then the package selection at the bottom disappears (is gone) and browsing for it will not make it re-appear.
Shown in screenshots.

What am I doing wrong here?
Thanks!

You just need to select your device in "Routers/Drives" first. Then select the folder that contains your ROS main package. Select packages you want to install. Then hit Install button.

see https://help.mikrotik.com/docs/display/ROS/Netinstall

I have already tried this and it is not working.
This is exactly what I am trying and have explained in detail in my post.

Also the link you provided are the exact instructions that I have used and understand which got me to the point I am at right now.
I can select the folder where the package resides but it does not show up in netinstall.
It even says there is one package in the folder as I have detailed.

The file is routeros-7.14.2-arm.npk and is confirmed to be a valid/good file.
I have used it to upgrade other routers via winbox.
I also tried 7.14.1
Same problem will not show up in netinstall.

In screenshot 2 ... select router first and then package ... or this still doesn't do the trick?

Also make sure that the routeros npk file you have available is for the CPU architecture of your RB750 (it seems that RB750 is MIPSBE but verify yourself).

The RG750 is mipsbe device.

https://cdn.mikrotik.com/routeros/7.14. ... mipsbe.npk

Not arm

Thanks!
I'll try that. Thought it was ARM.
But then also I can't seem to find a product page for the original RB750
And I would possibly take a hint from the newer RB750G? but product page does not have specs on arch.
https://mikrotik.com/product/RB750G#fnd ... ifications

This would also totally explain why I cannot update with Winbox LOL.
Complete newb here.

And of course this worked. (as expected).
Is there and old archived specs page for this old router?
I took a pretty long look for it before going about upgrading the firmware and could not find it.
Closest I found was the 750G which has no details about the ARCH.
And I incorrectly assumed it was ARM.
I feel stupid.
Thanks for the help on this one.

I guess I should have caught this on the 750G description "a new 680MHz Atheros 7161 CPU for increased throughput."
But was in the description that I skipped over and went right for the specs info.
I also looked over it quickly while spending a lot more time looking for any info on the RG750. (V1)
-Steve

Don't be sorry.
There are 4 versions of RG750

RB750
https://mikrotik.com/product/RB750GL
https://mikrotik.com/product/RB750UP

https://mikrotik.com/product/RB750G
And your device haven't any specs of what ARCH being used.

And the best of the thing is that you can do lots of stuff with the device and not brick it.
And now you have upgrade the RouterOS, you also want to update the firmware, that is like the bios in the router called RouterBoot.
You can do that in webfig,
https://192.168.88.1/webfig/#System:RouterBOARD

I'm a little confused on routerboot itself I think that newer firmwares include an update to routerboot no? I might be wrong but I spent some time trying to find that package.
Maybe I will need to do more.
And yes this box is purely educational.

So Maybe I have a 750UP?
The box itself label only reads RouterBoard 750
no "UP"

Yes the firmware(RouterBoot) is in the RouterOS, you can update just pressing Update in the Routerboard menu.

There like you say also RG750.. when i read the specs on RG750G I can read this.
The UP have USB port.

It’s probably the most affordable MPLS capable router on the market. With compact design and clean looks, it will fit perfectly into any SOHO environment. Comparing to RB750, the G version adds not only Gigabit capable ports, but also a new 680MHz Atheros 7161 CPU for increased throughput. Up to 580Mbps throughout with larger packets, and up to 91500pps with small packets!

And when i read this it seems like there also using RB750 Atheros7240 (ether2-ether5)
https://wiki.mikrotik.com/wiki/Manual:S ... p_Features