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Missing LPT1 on Windows 7 Pro System(s)

After installation of Windows 7 Pro on several upgraded computers in an office LAN environment with a shared dot matrix printer, the newly-upgraded computers are unable to print to the shared computer using a DOS program running in XP Mode that sends print data to the LPT1 printer port. In trying to diagnose this problem, I discovered that the LPT1 printer port is entirely missing from the upgraded computers with this problem. Another, non-upgraded computer with the same OS that *has* the LPT1 port is able to print to the shared printer directly from Windows 7 Pro. FYI (but this may not be relevant), in all these print situations, whether printing through XP Mode or from Windows 7 Pro itself, users are printing from a database accessed remotely via CATS Pajamas (a publishing database program) that has its own printer configuration that formats print files sent to the dot matrix printer and specifies LPT1 as part of the printer setup inside the database.

I am not sure how to install an LPT1 port to match the port found on the one computer in this office that can print to the dot matrix printer successfully through the remote database and without running the database access out of XP Mode. This would be ideal, since XP Mode uses system resources that slows other programs running simultaneously (of which there are several for all of these users).

All advice is welcome.
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So the printer is an LPT1 printer?  Or the software receives the print job over LPT1?  I would perhaps try a print server
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Norm Dickinson

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I realize I was unclear in my original question. The problem is that no printer PORT named "LPT1" appears on these two upgraded Win 7 Pro machines. On the one computer in the office that is able to print to that dot matrix printer from within CATS Pajamas *does* have an LPT1 port listed among Printer Ports in the Device Manager. Indeed, I think the step by Norm Dickinson is exactly how that one computer manages to 'talk to' the dot matrix printer through the LPT1 port. What I need to know before I can implement that step is how to go about adding an LPT1 printer port where none exists (on the two upgraded computers running Win 7 Pro that lack that port). This may be very easy, but I don't know how to do it and while I've seen some sites that talk about creating  one, none of them seem to involve the exact situation I face.
       I hope this adequately clarifies my situation.
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Still not clear. How do you connect this printer? Is it via a parallel cable, or do you use a network or USB connection?

If the printer uses USB or network, then Norm's suggestion should do the trick. If the printer uses a parallel connection, then you need either a parallel port on the PC (look on the back of the PC to check if one is there), or you need to use something like a printserver, as suggested by Knighsman.
The point of the Net Use command is to create a virtual printer port on the Windows 7 machines that do not currently have an LPT port installed.

Some software just points to LPT1, for example - others can choose between LPTs 1 - 3. Some have more options and others get into specific printer drivers to install. It varies a lot from one program to the next.

You may have to go into Devices and Printers and set up a printer driver, if one is not already installed. Then go into the Printer Properties, and Ports. Create a new LPT port and use it.

Give it a try.
find the lpt cards here :

assuming a desktop pc
Please see if this link is helpful to check whether LPT1 option is set or not.
Hi Norm, Nobus, Sandeep, hdhondt,
       Further clarifications:
hdhondt: the dot matrix printer is accessed over the LAN. It is directly attached to the file server that is connected to the passive network switch. Under Devices and Printers on the desktop that has no problems with printing to the dot matrix printer (it can print to it without running the CATS Pajamas program inside XP Mode, and all of the various kinds of files are formatted correctly when printed) the port assigned is identified as a USB port, and I think that is because the connection between the file server and the dot matrix printer is a USB cable.
nobus/sandeep/normdickinson: I understand the purpose of the Net Use command norm suggested I use. The problem is that when I look under the Device Manager's "Ports (Com and LPT)" section, only a COM port is listed. I assume that the Net Use command will not work if there is no LPT port listed in the Device Manager. Perhaps this is because there is missing hardware (implied by nobus' comment, perhaps?)? All I know is that the computer that successfully prints to this networked dot matrix printer *has* an LPT1 port listed in that section of the Device Manager. Let me add for Norm Dickinson that I have seen a ".dat" file on the desktop of that computer that contains the very Net Use command string he had recommended. When I use that on the other computers, the printing problem is not resolved/overcome.

I hope this helps clarify what seem to be the only differences between otherwise identical desktop computers (except that the one that can print to the dot matrix printer is an older model from the same manufacturer). What I have read about LPT ports suggests one possible solution: that the parallel ports have to be enabled in the BIOS in order for them to show up under the Device Manager's Ports section. Could this be the solution I've been looking for?

Sorry for my ignorance (which no doubt persists!).
what pc modle is this?  or mobo model?

>>  Sorry for my ignorance (which no doubt persists!).   <<   don't be sorry  - my ignorance is probably biggert than yours..
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Norm: Thanks for the tip. I will do that shortly and let you know what happened.
what pc model are these?
Norm: I tried this but the printer driver for this networked dot matrix printer has all port options other than a "USB002" that has this description: "Virtual printer port for USB".

nobus: the computer is an HP ProDesk 600 G1 SFF off-the-shelf model.

I don't know if this will help, but on the desktop that *can* print to this printer, the settings for the networked printer are the same as for this one. The only difference is that in the Device Manager under Ports there is both a COM port and an "ECP Printer Port (LPT1)" listed.

I am going to check BIOS settings to see if the parallel port for this mother board is disabled.

If any of the above helps, please let me know. Meanwhile, I am trying to find out what batch files run at bootup on the one computer that prints without difficulty to this networked dot matrix printer. For that, I need to get an administrator password from whoever managed this office network in the past. I'll get back to you if that turns up any information that seems useful.

Norm/nobus: here's some new information. I see that the desktop that has an LPT1 port and prints fine to the dot matrix printer on the network is an Optiplex 380, which has a parallel port. The two new desktop computers this organization bought and that do *not* print to that printer, and seem to lack an LPT1 parallel port, show no parallel port in the manual for that model (HP ProDesk 600 G1 SFF). This may explain the source of the problem. Do you think that if I got a parallel port expansion card, this might solve the problem?
the parallel cardwill solve it - i assume the printer is connected directly to that port?
just make sure the card supports your OS when you buy it - but that should be no big problem
nobus: I will confirm that the parallel port expansion card (probably a PCIe card) will work both with this motherboard and with Windows 7 Pro.

The printer is *not* directly connected to the parallel port, but rather, these machines use a script that Norm mentioned earlier (Net Use lpt1 \\printserver\printer /persistent:yes). That instructs the computer to go out looking for that dot matrix printer, but in order for the command to work, there must be an LPT1 port active on the computer, and that is what has been missing.

I will update you once I've acquired the appropriate expansion card and tested it.
ok - post result
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These answers should resolve the question.
The LPT1 card did not fix the printing problem. We can print to the networked printer through the Windows 7 driver, but the font indicated in the printer viewer for this database program is very different than the one that the EPSON DFX-9000 ESC/P prints out. We have tried altering the default font on the printer itself, but that made no difference. The presumption is that the windows printer driver alters the font since most print drivers operating within the Windows 7 environment assume the target printer is a laser printer with proportional fonts, not fixed-width fonts of the type that is appearing onscreen in the database program's print viewer.

So I now have a new question: we have tried the "net use" command suggested up above here. When we apply the command and then type "net use" plus a return in the elevated command prompt window, we see what we should see: that the LPT1 port is mapped to the networked DFX-9000. However, when we attempt to print to that port, we get an error and nothing prints. Any idea why the mapping would not work, given that the "net use" command reports that the mapping is in place?
Can you print as Administrator?
What is the error message?
What happens when you try the command "COPY text_file LPT1"? Do this at the same DOS prompt as NET USE
I tried the copy string you recommended and got an "Access Denied" reply.

The error message when attempting to print to the LPT1 port from the DOS program is PRINTER ERROR (an error message coming from the DOS program, not Windows).

Does any of this help?
Try opening the DOS command as administrator. Click the Start menu and type CMD. Right-click it and select "Run as Administrator". See if that helps.

Also, try giving Everyone write access to c:\windows\system32\spool\printers.
I did run CMD as an administrator. Do you mean for me to give everyone write access to that location on the server computer (the one that has direct access to the dot matrix printer)?
Spooling is done on the local computer, so that's where the access should be.

If that does not help, try using LPT2 instead of LPT1.