Windows 95: Windows protection error after setup

Not open for further replies.


May 7, 2011
I am trying to set up Windows 95 on a VM using Microsoft Virtual PC 2007 with a 8 GB VHD. Everything works fine until it finishes setup, but it when it tries to start Windows for the first time, it says, "While initializing device IOS: Windows protection error. You need to restart your computer."

I have tried booting up in safe mode and have formatted the VHD and reinstalled it several times, but I can't figure out why it won't work. It worked fine once before, but the hard drive it was on went bad, so I have to set it up again.

Thank you for any help/solutions.

sdfox 7

Mar 6, 2011
Usually IOS results from too much RAM; generally you'll get this error with more than 512MB RAM.

Try reducing the available amount of RAM on the virtual setup and try again. Windows 95 is a very fast OS on hardware from 1998 and up, so I wouldn't allocate more than 384MB RAM.


Dec 7, 2012

Have you tried disabling Hardware Virtualization? That mostly fixes the problem :wahoo:


Dec 10, 2012
Disable Hardware Virutalization. Also, don't allocate more than 384MB RAM for the virtual machine. If you try to install it on a physical computer, it will probably crash because you have a CPU with P6 support. If you use a Windows 95 OSR2.5 disc, it will not crash.


Jan 2, 2013

Holy *** man, thanks a damn lot. That solved my problem. You're my hero of today =)


Nov 22, 2010

I just started my virtual Win 95 for the 1st time on VMWare 9. The Windows 95 Logo comes up fine but then I get the same error " Windows protection error"
I have set my RAM at about 250 MB. It doesn't help. How do I disable Hardware Actualization?. Is it done within the guest system in VMWare or in the main Host system? ( I am on Windows 7)




Michael MacDonald

May 15, 2014
if anyone is still having troubles here's an alternative solution
(this is what I had to do to get it working on windows 7)

installing windows 95 manually without the floppy setup disk

what you need:
.DOS on a floppy or on an image (.flp .img)
.Windows 95 cd
.VMWARE player (it's free) or virtualpc (I recommend VMWARE)
.Magiciso (the free trial version will do)
.a copy of MSCDEX.EXE and oakcdrom.sys (both can be found online)

step 1

create a new virtual machine (make sure to add a floppy image drive if you are using vmware)

step 2

put your dos floppy/image in or mount it and install dos

step 3

download and install the free version of magiciso
open magic iso
go to new - floppy - 1.44

find a copy of mscdex.exe
find a copy of oakcdrom.sys (generic cd rom driver that works with dos.. might have to try another if it doesn't work)
RENAME the oakcdrom.sys to cdrom.sys

drag both these files into magic iso on the floppy disk we just created

save the file

close magic iso

find the file we just saved in your explorer

change the extension from .ima to .flp (if you are using vmware) or .img (if you are using virtualpc)

(if you can't see the extensions you're going to need to change your folder options to show extensions)
google it. it's easy to do

step 4

go back to your virtual machine
mount the floppy image we just created

copy mscdex.exe c:\
copy cdrom.sys c:\

(don't forget to rename oakcdrom.sys to cdrom.sys in step 3)

step 5

find config.sys in your c drive


edit config.sys

now add a line that says this

device=c:\cdrom.sys /d:mscd001

exit and save

step 6

find autoexec.bat in your c drive


edit autoexec.bat

now add a line that says this

c:\mscdex.exe /d:mscd001

exit and save

step 7

restart the computer or virtual machine

step 8

we're still not done yet

now move to your c drive and type

mscdex.exe: /d:mscd001 /M:5 /V /L:d /S /K

(this part /M:x refers to the amount of buffers your drive has.. it's either 4 or 5. usually 5)

step 9

create a blank floppy image either in vmware or magic iso then mount that new one

put your windows 95 cd in the cd drive



step 10

it should be booting windows 95 now

now you might run into troubles when it tries to install the other drivers
it might ask you for windows floppies even if you're using the cd version
which I never understood

but anyways, you can find all of these drivers on the windows 95b cd if you have it
they're all in cab files

so you'd need to extract them 1 by 1 and put them on floppy images to use them.
(huge pain)

but I actually just got it to load the drivers off the win95 cd by just trying it over and over again until
it worked. it might have been because I either did or didn't restart after putting in the windows 95 cd
can't remember, but I'd try both if you're having trouble

all in all windows 95 is incredible wonky to install in a virtual machine. I highly recommend using VMWARE
and not virtual pc for this one.
If you didn't have a hard time installing this.. you got incredible lucky

make sure you check to make sure windows95 is seeing your cd drive
if not go to the add new hardware wizard in the control panel and see if that detects it

(note: I tried it first without installing dos before hand and was running into troubles even though I had build the autoexec.bat and the config.sys correctly. Installing ms-dos first made the installation process a lot smoother)

Michael MacDonald
State of Psychosis
Not open for further replies.