The Aztech IDE CD driver for NT 3.1 has a bug for not reading ISOs below a certain size (The Device is not ready)

To make readable CDROMs for NT 3.1 do the following:

Make a copy of an already made 100MB (or above) ISO image in the same folder as the former but do not rename the copied ISO!
Erase the contents of the copied ISO and save but still don't rename it.
Open it and then place your data there, save and happyness with CDROMs working on NT 3.1, now you can rename it.

Note: This won't work if you make a copy of the already copied file.

Or create some files of a size larger than 500MB, put them in an ISO, and then erase the files from that. Probably more efficient than downloading Windows 7 ISOs. Anyway, Windows 7 is shipped on DVDs, so they'll be too large.

I used the Windows 7 Build 6469 ISO/DVD, it was like 2,470,00KB big, erased its contents, saved and still read as that size, and NT 3.1 reads the ISO without any issues

Hmm, okay then. I don't really want to have to download 2GB worth of Windows 7 beta JUST for the purpose of erasing its contents for use by NT 3.1.

I do that instead, it's more efficent and also good, this topic should be stickied because of users having issues with CDROMs with NT 3.1.

Just create a 700MB ISO_9660 ISO. Fixed.

Ok, but when I erase the contents, it becomes a little 50KB ISO file and won't be read.