This is how I install Win9x on my systems. You may have a different way, and hey, that's great! This is just how I do it.

Something to note is that I mostly own systems that are very heavily minmaxed. That is to say, they're not super era appropriate, it's just XP-era hardware that happens to have 9x driver support. Older systems on the fringe of having 98 support might struggle with these instructions. There are also other ways of going about what I do here. I'll try to point out other paths you can take instead as need be.

This guide involves booting the system into a mini XP environment and doing all the prep work there. You don't necessarily have to do this, but I find it handles two problems at once: I can prep the drive in XP, and also look at the detected hardware and see what I need to grab drivers for. You can also just prep the drive in another system, that works as well.

Anyway, without further ado:

For this I am going to assume you are running a semi-“modern” drive, that is one in excess of 64GB capacity. While you CAN prep drives by just doing it the old way (using fdisk and letting it roll), I find this tends to cause issues with larger capacity drives. Trying to prep the drive in a modern system will also cause issues, sometimes the system will format it as a GPT drive (GPT standing for “GUID Partition Table”) which causes older operating systems to absolutely flip out.

So for this, as stated above, I like to prep the drive in situ by leaving it in the system it'll be going into and starting up a mini-XP instance (I use Hirens BootCD 15.2) to format it with XP's built-in formatting tools.

However, depending on the capacity of the drive (if it's bigger than 32GB) you may notice a small hangup: XP's built in formatter will only let you format the drive as exFAT or NTFS, neither of which will work for Win9x! There are command-line ways to get around this from my understanding, but I opt to use a convenient utility instead: GUIFormat.

This will run on XP and newer and formats the selected drive to just basic FAT32, regardless of capacity. This utility will gladly run in the mini XP instance Hirens gives us, so I keep it on a USB stick (or if the machine in question has a network card, I keep it on a local FTP server).

Double click it, aim it at the right drive (usually C: but make sure) and let 'er rip.

(Again, you can do this on another system entirely if you have a way to access the drive on that system, just if you're doing this on a modern system make sure the drive is formatted with the MBR partition map.)

Sidenote: In case you're curious, the reason we don't use something like a live Linux environment with GParted is it does something with the drive that Win9x doesn't like. Try as I might after formatting a drive as FAT32 in GParted, Win9x doesn't recognize the drive and demands it be reformatted. Which is why I like to just stick with a Windows system for this.

At this point you should have a blank FAT32 disk. You might be tempted to just put your install disc into the drive, boot, and install 9x the old fashioned way. We're not going to do that. There's a better way.

Assuming you haven't rebooted out of the XP environment yet (or are doing this on a modern system), you just need a way to get the win9x folder off the disc and onto the freshly formatted disk you just prepared. This is as simple as just popping the disc in (you can eject the XP boot disc/Hirens if that's what you're using, it won't care) and dragging/dropping the folder on the root of the hard drive you're installing to.

You can also just grab an ISO of the disc and crack it open with something like PowerISO and pull the win9x folder out that way too.

Either way, you want that win9x folder on the root of your C: drive.

Now would also be a good time to make a folder called something like “install me” and load it up with programs/drivers/what have you while you can. If you're installing Win98 on a USB-capable system I do highly recommend grabbing the Windows 98 Mass Storage drivers. It'll make your life easier.

WARNING: If you're installing 9x on a system with more than 512MB of RAM, make sure you grab a copy of PATCHMEM and put it on the root of your C drive. You can also put it on a floppy disk. Just make sure it's somewhere accessible within DOS.

You can also do the copying part from DOS, if need be. Very quickly:

1. Boot into DOS, with CD support if booting from the Win9x install disc.
2. When at the prompt, type C:. You should now be sitting at a C:\> prompt.
3. Type mkdir win9x (This differs based on Windows version. win95 for Windows 95, win98 for Windows 98, and win9x for Windows Me. Substitute accordingly.)
4. Type cd win9x (substitute as needed per previous step). You should now be sitting at a C:\win9x> prompt.
5. Type D: (or whatever drive corresponds to your physical disc drive or drive emulator if you have one). You should now be sitting at a D:\> prompt.
6. Type cd win9x (once again, keeping in mind the substitution you made in step 3)
7. Now type copy *.* C: and watch the magic unfold.

(This might sound confusing, like you just copied everything to the root of your C drive! But DOS remembers what directory when you were looking at when you tabbed over to your optical drive, and assumes because you didn't specify a folder in the copy command that you just want to copy the files to wherever you last were when you were looking at the C drive.)

At this point, you should now have a hard drive with a win9x folder at the root.

To kick things off, boot into DOS (either via boot floppy or using a Win9x install disc), and once booted switch over to your C: drive (just type C: once in DOS), type cd win9x (substituting as necessary depending on what 9x variant you're installing), and then kick off Setup with setup /is.

You'll now be guided through a normal Windows setup, but instead you're installing from the hard drive instead of an optical disc! This has the benefit of telling Windows to just pull files from the win9x folder when it needs them rather than making you find the disc when it needs to reference it (for things like driver installs and the like).

For systems with more than 512MB of RAM: I hope you heeded my warning earlier about getting a copy of PATCHMEM and putting it somewhere accessible from DOS, because you're going to need it now. If you have less than 512MB of RAM you can ignore this part and continue with setup as normal.

You'll want to keep your DOS boot media (be it the 9x disc or a floppy) handy.

You're going to proceed through the first part of setup (where it asks for the install destination and what features you want) as normal. Let it do the first reboot and proceed back into setup. Proceed through this part (you should be entering your license key during this part), and when it goes to reboot again, insert whatever media you're booting DOS from. Do NOT let it boot from the hard drive.

Once you're back in DOS, navigate to wherever you stuck PATCHMEM and run it. (Just type “patchmem” once you're in the folder containing it.)

You should get a success message. At this point you're free to let the machine boot from the hard drive and continue Windows Setup as normal.

If you made it through all that, you should now be sitting at a freshly-installed copy of Windows. Besides installing drivers, there are some things you should do, here:

Make sure DMA is turned on for your hard drive. If you're running a SATA drive like I am, make sure the drivers for it are installed first. After that, right-click My Computer and click on Properties, go over to Device Manager, and find your hard disk (it'll probably be listed as “Generic IDE hard disk” or something of the sort.)

Right click it, click the Settings tab, and make sure DMA is checked. If it's greyed out, again, make sure the proper drivers are installed (and if it has to be turned on in your computer's BIOS, make sure DMA is flipped on there too).

For SATA disks especially, DMA being off will cause them to perform horribly, and oftentimes even once the proper drivers are installed it doesn't self-enable DMA, you need to do it yourself.

Run updates! Windows Update Restored is an awesome project that has archived a good chunk of updates for these older systems. You'll need a network connection to do this, of course, but it helps to patch some of Win9x's quirks and stability problems.

For WinMe users, I find WUR didn't want to work right with my Me system, but there's a community-made update CD over on Archive.org that does much the same thing as WUR does.