"Security failure 8" error with LPT1 dongle

[wcpesp]

Question

Hello All, I'm a new user of DOSBox-X, just installed it today on my new (Dell 2025 build) Win11 machine.

I would like to run an old (~1995) CAD program that requires a hardware dongle on the printer port (LPT1). That old CAD program works fine right now, on an old Win95 machine, running in "DOS mode". The program itself, says its for DOS and I can launch and run it from the DOS prompt (on the old machine), just like I did in the 1990's. I was hoping that I could somehow run that old program on my new Win11 machine so I can finally get rid of that old computer that just gathers dust and takes up so much space.

My Win11 machine has an aftermarket PCIe-x1 parallel port card, with fresh drivers, and it works great on its own. I mounted the dongle on it and re-started my machine, then installed DOSBox-X. The DOSBox-X GUI is beautiful and I played around with DOS prompt, works great, zero problem.

I then launched my old CAD program and DOSBox-x threw an error that said:
WARNING: Security failure 8
Note: Program terminating due to severe error.

Do I need to configure the printer port, or change a security setting in DOSBox-X?

Any help or guidance would be greatly appreciated.

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[joncampbell123]

For Windows, you will need ioport.dll and ioport.sys. I don't know if that still works under Windows 10/11 though.

You may also want to try running DOSBox-X under Linux instead of Windows.

[wcpesp]

Thanks for the quick response.

I'm pretty capable with a computer, but I dont know what I am supposed to do with ioport.dll and ioport.sys.

Please explain or point me to where I can get the answer. Thank you!

[wcpesp]

Good morning Jon, I did alot of Google research last night, there are many people in nearly the exact same situation as myself.... 1990's industrial software/hardware combo, with parallel port security-key dongle Trying to move their software to a modern machine using a PCIe adapter card It seems that this is a really tough challenge, basically related to the port addressing schemes. I think I will try loading Win95 on VMware, to emulate the old machine. If that doesnt work I will just drop this project, while considering myself lucky to still have the old, original machine and setup running, even if it is taking up alot of space. Feel free to delete my entire post from your forum, since it was a dud and will likely go nowhere. Thanks, Bill On Sunday, March 29, 2026 at 08:35:45 PM EDT, Jonathan Campbell ***@***.***> wrote: joncampbell123 left a comment (joncampbell123/dosbox-x#6180) For Windows, you will need ioport.dll and ioport.sys. I don't know if that still works under Windows 10/11 though. You may also want to try running DOSBox-X under Linux instead of Windows. — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>

[Torinde]

Try setting in dosbox-x.conf file:

• parallel1: realpt realbase ... ecpbase ...

You can see all .conf settings in dosbox-x.reference.full.conf and you should be able to find the base addresses via Device Manager.
Some explanations are here.

I had success in Win10 with directserial realport (which is the COM equivalent of your task) and I don't see ioport.dll mentioned there, if it applies also to COM, probably it comes standard in Win10 or the USB-to-COM driver I used.

[wcpesp]

Thanks for the suggestion Torinde, I will try it!

[wcpesp]

My device manager looks like this....

I cannot find any reference to "ECP" anywhere, whether clicking right-button or left-button.

I editted the DOSBox-X config file to include this line:

When I tried to run my old program in DOSBox-X, I received the exact same error as yesterday.

Did I make a mistake with my configuration line?

[wcpesp]

I also tried using this line in the config file, instead......

parallel1: printer realpt: 4FF8

It still produces the same error.

[Torinde]

Did you read the .conf file?

Additional parameters must be in the same line in the form of
parameter:value

Also I made a typo - it's not realpt, but that's why you need to read the .conf, not just copy from my comment.
Another typo I made - it's not parallel1:, but parallel1 = just like any other DOSBox .conf setting...

So, I assume parallel1 = reallpt realbase:378 ecpbase:???

4FF8 doesn't look like LPT address at all, that's probably some PCIe chip thing.
What do you have in "Port settings" tab?

[wcpesp]

Thanks for the follow-up but after researching and running vDos, DOSBox-x, VMware and Virtualbox....I've dropped the idea and will just continue using my old 1990's 486 Win95 PC for the purpose. It still works perfectly.

I spent about a day and a half reading forum posts and articles on this subject, with many people in the exact same situation as myself. I could not find any success stories when using PCIe cards and virtual machines to utilize LPT1 at the old legacy address that the old dongles require.

I appreciate your willingness to help but I no longer need it.

Oh and by the way, yes....I did read the config file instructions after my last post, found the typos, re-tried, still didnt work.

Thanks again, carry on..........