I've been using Puppy on various laptop/netbooks for years.
My old (ancient) ex-corporate,Dell Lattitude threw a graphics card wobbly so I bought a replacement with no hdd, memory, battery etc. and I swapped over the hardware.
On attempting to boot I got a "No GRLDR" message.
I tried my trusty USB (made using unetbootin) loader and I got the same result.
I am not trying to dual boot, there is no Windows software anywhere near me, I'm Linux only.
I've never experienced this before and I've swapped and changed distros and hardware scores of times previously.
The laptop I'm using now has the same puppy installation and it has GRLDR in the same section as menu/lst and menu-advanced.lst but I can't see it on the boot USB.
I think that the fresh D420 is operational so I'm wondering if this is something in the BIOS. I've been unable to find a post with a similar problem, they all seem to be related to dual booting.
The netbook has no optical drive and the hdd is a 1.8" thing making it difficult to try another distro on another drive.
Any ideas gratefully recieved.

Details on "GRLDR" at the link below which gives some causes and solutions to the problem.

https://neosmart.net/wiki/cannot-find-grldr/

Thank you yancek,
I've come across that site before, it appears to be almost entirely related to various windows o/s and dual booting which I don't think applies in this case. I have no problem with windows, I don't have any microsoft stuff. For a reason I can't understand, the fresh Dell D420 cannot see the GRLDR on my hdd - the previous one could, it worked perfectly until the graphics went west. The GRLDR is not obvious on the USB boot stick (or at least, not obvious to me). I'm guessing that I need to copy a GRLDR to my hdd but as I can't boot it I need to get a live distro working on the Dell. The USB stick doesn't work so I'm going to try the old way and connect an external optical drive and try a CD.
Thanks again for your input.

I have never used Grub4Dos so I can't do any more than wish you luck. Grub and Grub2 always worked well for me.

Thanks jancek,
I'll scratch around and see what else I can find.

Solved it!
I always assumed that a unetbootin USB would have some sort of loader built in, seems I was wrong.
I used a distro on another laptop to install Grub4Dos (the only one I have any experience of) on the USB drive and a bit of fishing around in the advanced section of the boot options resulted in the required result.
Thanks again jancek, I hope this helps anyone else experiencing a similar problem.

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Unetbootin uses syslinux/isolinux as a bootloader as do most Linux Live CD/DVD's so I would not expect to see anything related to Grub4Dos on any of them. Might be some Grub files but they generally are not used to boot a CD/DVD with a 'live' system.

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