Hi there, I recently acquired a 5300ce and I'm planning on getting a new install on it. However it won't boot from any floppy I put into it.
I've done the floppies from the 7.5.2 and 7.5.3 disk sets. In both instances, it briefly shows the happy mac face before it ejects the floppy and returns to the ? icon. Is this something to do with its HDD?
Hard to say, but if you know the media is good you may have to look at cleaning the floppy drive... a proper service of that may help.
Maybe try to get an external SCSI CD-ROM drive to install Mac OS right off of a CD-ROM drive(Mac OS 8 or 9 comes in mind).
Me, recently I replaced the internal hard disk drive of a PowerBook G3 ("Pismo") with an IDE-to-SD card adapter, getting up to 128 GB space. The computer sees it still as bootable hard disk drive. This was the idea to replace old mechanical HDD by modern ones. Works fine so far.
Since the internal HDD of yours should also be connected by IDE/ATA, you could try that also.
I've done the floppies from the 7.5.2 and 7.5.3 disk sets. In both instances, it briefly shows the happy mac face before it ejects the floppy and returns to the ? icon. Is this something to do with its HDD?
Perhaps. Are you trying boot from floppies for this Mac from a universal Mac OS release?
In which case you would need to add the System Enabler "PowerBook 5300/2300/190 Enabler" to the mix. Or get the original boot floppy for this particular model, which would have the enabler on board (a cut-down version of it, going by page description). Install CD's for this Mac model would also have the enabler and carry the correct boot floppy image for it, I would assume.
Boot floppies from a later OS (7.6+ ?) would likely not require any enabler.
I also used the original boot floppy and that gave me the same response as before. Curiously, the 7.5.3 Disk 1 did boot up to the installer screen, but it said the hard drive that I wanted to use (4GB Toshiba IDE) was locked.
Not a Apple branded drive, but an ex PC drive?
I would custom build a Disk Tools floppy with the approriate enabler + a patched Drive Setup and see if that makes a difference.
Does it currently have a bootable OS on the IDE drive?
You could also remove the drive and check its jumper settings, which should be set to master or single drive only, for this Mac.
Perhaps this would also be a good opportunity to test the drive in another computer and reformat on that machine (if at all possible for you to do so).
The drive itself was ex-PC but reformatted to Extended on an iMac running 10.4.11 via IDE-USB adapter, getting the locked warning.
Also as I'm new to this kind of thing, what would I need to include on the floppy specifically?
reformatted to Extended on an iMac running 10.4.11
That is an immediate problem. HFS+ (Extended or HFS Plus) isn't recognised on Mac OS before version 8.1
To run any earlier Mac OS the drive will need to be formatted as HFS, not HFS+ - and you will need to do this before anything else if running an earlier Mac OS on it, is your goal.
With the drive formatted as HFS only, then you should be OK using the "Disk Tools" floppy that came with the correct original OS for this Mac (if restoring to an original OS condition is what you want), Otherwise you could install 8.1 (or later) on it without reformatting.
You can try booting up with a Mac OS 8.1 (or 8.5) "Disk Tools" boot floppy from a universal install set, this shouldn't need an enabler and will recognise the HFS+ partition. You could then run "Drive Setup" which will be on the 8.1 boot floppy, and reformat the drive to HFS, should you want to run the earlier 7.5.3 OS. - After this, you should be able to use the install disks from the original source to install the earlier OS.
With HFS, it would also pay to partition a 4GB drive to smaller sizes - e.g.; 4 x 1GB, as files stored on an HFS disk drive consume far less disk space, the smaller the partition size you use.
Note: Mac OS 8.1 came with two "Disk Tools" floppies in their universal distribution (as floppy disk images on CD distributions). One for booting Macs with SCSI built-in drives and one for Macs with IDE drives, you will want the latter.
Could you link to one of those 8.1 floppy sets? I could only find the 8.0 on this site and I can't open them because they're in .dsk format.
I was referring to the bootable "Disk Tools" images found on the Toast CD image for 8.1, located on the Mac OS 8.0 & 8.1 page. The 10th DL listed on that page, named "Mac_OS_8.1.zip (238.99 MB)".
But I'm also thinking the Disk Tools floppy image found on the Toast CD image for 8.5, located on the Mac OS 8.5 & 8.6 page would be a better choice. The 8th DL listed on that page, named "Mac_OS_8.6.toast_.zip (343.49 MB)".
You would need to mount the Toast CD image, locate and write the Disk Copy image of the Disk Tools to 1.44MB HD floppy disk. Are you in a situation to do this? i.e.; Have a computer capable of writing to floppy media?
Fortunately, as it happens, I was cleaning out some inventory in my place of business (a used computer parts store) and lo and behold there was in fact THE 5300ce's specific Disk Tools disk lol. Thanks so much for the advice anyway. 
As you already have a USB-2-IDE adapter, I would give it another go and put together a working System on the PB HDD.
The last OS to write HFS from user land was Leopard 10.5.
Therefore a VM running 10.5 Server looks most promising to me.
A bootable image is here: (if you prefer not to install from scratch)
https://mega.nz/#!F1FDgT7D!ssfE_13FkA7WzK_53YYS_bAevLhKoCDdOepq6pSx8sw
(user/pass for the server is mac/macosx.)
You will need VMWare Fusion to run it on your Mac, the trial version should do.
Your IDE adapter should be assignable to Leo Server easily, so you may partition/initialize your PB drive and copy a bootable system onto the drive.
If need should be, someone may prepare a bootable image (with a System of your choice) to copy over its content.
Finally, after moving files to the PB HDD is done, don´t forget to open System folder once and close it again, to "bless" it.
VMWare may look like a long shot, if you are not used to virtual machines, but Leo Server is nice to have, even more if you need a helper "Mac" for oldish Macintosh. You can even write HFS HD floppies from the virtual machine once a USB floppy drive is connected.
I had kind of the same problem with the floppy drive in my newly acquired Mac SE when it arrived. Initially it would seem as if it tries to read the disk and then suddenly it stops. If the OS is booted, it would usually ask for initialization of the disk (though that would fail too). First thing - can you rule out a defective floppy disc by testing it on another device?
If that works, it narrows down to the floppy drive itself. They are actually quite robust if you compare them to the CD drives in many G4s, but still - they don't get any younger. As a rule of thumb: Floppy drives want to be used! If you don't use it often and had it lying around for some time, it's likely that dust and dirt settled. That's why I use my floppy drives every so often.
Good news is you can fix that yourself. But you've got some legwork to do - that is, cleaning the floppy drive head with pure alcohol. I've done that last week with my Mac SE floppy drive and it works again. Just a word of warning - stay away from "cleaning floppies", they're rubbish and do nothing. (best case)
On YouTube you'll find detailed tutorials on how to clean a floppy drive head. You need to be careful not to bend the drive head or you'll easily ruin your floppy drive beyond repair. Other than that, it doesn't require much skill and can easily be done by anyone with a calm hand. It's easy to rescue a lot of floppy drives that otherwise get thrown away. From my experience, 3 out of 5 defective floppy drives today just need a cleaning. Then there's the broken gears problem (no ejection) but these can be fixed too thanks to 3D printing.
Go ahead and disassemble the book and clean the floppy drive. Almost positive it will make it work again
