Bootmgr is missing error - how to fix?

Everything was running smooth on my HP laptop—I’ve got an HDD and an SSD tucked away in the DVD drive slot—and then, out of nowhere, this error message pops up. It’s driving me nuts. In Disk Management, everything looks perfectly fine; I can see both drives sitting there just waiting to be used. But the second I try to actually run an installation? Poof. Gone. When I boot from the optical drive, it only sees the HDD. So, I thought, "Fine, let's go old school," and I burned a bootable USB using Rufus, but even that thing acts like the drives don't exist. I'm at a total loss here. Does anyone know how to flag that SSD as a logical disk or something? I’m honestly running out of ideas.

?? What kind of DVD drive are we talking about when there's an SSD sitting in its spot instead?
?? Which OS are you planning to install?
?? What specific model of HP is this?
?? Are you trying to run the installation via a USB boot?

wearymason4 said:-- what DVD drive are you talking about when there's an SSD sitting right where it should be?
-- which OS are you even trying to throw on there?
-- what kind of HP model are we dealing with here?
-- are you actually trying to run a bootable USB install?

So, here’s the deal—I pulled the SSD out and used the DVD drive to get Windows 7 onto the HDD. Everything seemed fine until I made a bootable USB, but now when I try to boot from it, it just hits the drive and... nothing. Total dead end. It's an HP 250 1 wy08ea. Maybe I messed up the drive designations, or maybe I overdid it by resetting the BIOS to defaults? Who knows.

Dammit, I’m running into a headache here—USB booting is acting up again. ImgBurn is being completely useless; every time I check the "bootable disc" box, it starts demanding some kind of boot image. Like, what am I even supposed to upload there?