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USB > Parallel port adaptor for a software Security key

We have an old version of barcode printing software that has a parallel port security key.  The desktop that the software is running on is dying so we were able to find (amazingly) the installation file for the same version of the software and we were able to successfully install it on a Win 10 Laptop using compatability mode.  Of course the laptop does not have a parallel port so we bought a USB > Parallel port from Amazon.  Unfortunately, the software still does not see the key when it is plugged into the USB adaptor.  We are about to give up but thought I would post this just to see if maybe there was a windows setting or something that someone could suggest that might make this work?  Crazier things have happened!!!   Thanks for any suggestions!
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The software is written in such a way that it wants to "directly talk" the the LPT port. The USB interface "interferes" with that. The reason most things work on such a USB>LPT adapter, is because if the software "talks" to Windows (instead directly talking to the hardware), it usually works. That's why for printing (in Windows, NOT DOS!), it's usually a 100% guaranteed solution)
You might have better luck with a full hardware solution:
But even then, it depends on how strict the old software is written.
Dr. KlahnPrincipal Software Engineer
Kimputer is correct.  What the USB to IEEE-1284 adapter does is present the old-style printer on a USB port, which is usually something like USB001: rather than the LPT1: which old software expects.  Most Windows printer drivers will tolerate this.

Now in the old days it was possible to rig around this by telling the system something like NET USE USB001: LPT1: at command level, but it was a long time ago (20 years) and I'm sure things have changed since then.  Nor would I expect that to work under Windows 10, given the strict driver interface.

As Kimputer says, the approach most likely to work without fiddling around is to buy a cheap PCI or PCIe parallel port card, make sure that it is set to the LPT1: address (they usually come set for LPT2: or LPT3:), and see if that works.  But don't be surprised if it does not, because Windows 10 is very protective of devices.

If the only reason for this system to exist is to print barcodes, I'd drop trying to get it to work on W10.  I'd get an HP T5740 thin client, load Windows 7 on it, and let it serve anything on the network that wants to print barcodes.  The T5740 has a real line printer port and Windows 7 was not so protective of devices.

Side note:  At some point this device will get to a point where it can't be made to work no matter what.  It would be prudent to start seriously looking (viz., not "we should really do something about this someday") for a replacement.
What company is the Parallel port key from?

 I had this issue several months ago and I had to buy an older computer that still supported XP and installed a Parallel port card.  While the software installed just fine in Windows 10 and Windows 7, there were no "modern" drivers for the parallel port key on the new system.  It would not detect on through a parallel port card or USB to parallel adapter even with Windows 7.
Dr. KlahnPrincipal Software Engineer

On the really old dongles they did not detect as devices.  They were completely passive until interrogated by the application software.  Indeed, most of them were designed so that a printer could be plugged into the other side of the dongle and work normally; this prevented having to buy a second parallel port for the dongle.
Yes.  Many of those parallel port dongles existed from the late 80s through the 90s.  Eventually, they got away from those, because the Chinese had great success in reproducing those keys for the Asian market.  I saw one of the fakes when I visited once, and the "owner" paid a hundredth the price for his software and was bragging about it.
Distinguished Expert 2019

An option might be to virtualize thr old and fridge the parallel port to the host connected one.

As others noted he issue is whether the requests are making through the USB to ... Conversion.

At lest you know that you can install the software in compatibility mode, get an older/used sff system that ins lodes a parallel port and see if that provides for ...
The other issue compatibility mode of the software might try to detect the lpt1 port during install
The USB to opt might not be mapped at the same memory location as the ...
In device manager, look at changing its memory...