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I do not understand your question.

This is a simple print feature available on most ink printers, manually or with laser printers with a duplexer.

Can you rephrase your question or tell me exactly what you are trying to do, please.

I cannot use a duplexer

I cannot use a duplexer. It is not in my printer

All of my standard print options, word perfect, word and another all do this, it is in the additional options, for a two sided document.
My 30 dollar lexmart printer I carry in my work truck will do it.

Chuck is right, when you bring up the PRINT OPTIONS to print a long document in your program (Word?), you will often find these options. It is completely up to your particular printer, or you can even do and odd pages/even pages to do a manual sort of duplex printing.

Here is an excerpt from my Word help file:
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Some printers automatically print on both sides of a page (automatic duplex printing); other printers allow you to manually reinsert pages to print the second side (manual duplex printing); and some printers do not support duplex printing at all. To find out whether your printer supports duplex printing, you can check the printer manual, contact the printer manufacturer, or check the printer's properties by clicking Properties in the Print dialog box.

To find out whether your printer supports duplex printing
The options in the Print dialog box can vary depending on your printer options and configuration.

You can use the following clues to determine whether a specific printer supports duplex printing:

• Check your printer manual or consult your printer manufacturer.
• Click the tabs in the Print dialog box and review the options. If options such as print on both sides of the paper, duplex printing, or two-sided printing appear on any of the tabs, the printer probably supports automatic duplex printing.

Notes

• If you are printing to a combination copy machine and printer, and the copy machine supports two-sided copying, it probably supports automatic duplex printing.
• If you have more than one printer installed, it's possible that one printer supports duplex printing and another printer does not.

To manually set up a printer to print to both sides of a sheet of paper

With some printers, you can use the Manual duplex check box under Printer in the Print dialog box. Word will print all of the pages that appear on one side of the paper and then prompt you to turn the stack over and feed the pages into the printer again.

You can also use the following procedure to set up your printer for manual duplex printing:

1. On the File menu, click Print.
2. In the lower-left corner of the Print dialog box, in the Print box, click Odd pages.
3. Click OK.
4. After the odd pages are printed, flip the stack of pages over, and then in the Print dialog box, click Even pages.
5. Click OK.

Notes
Depending on the printer model, you might have to turn and reorder the pages to print the other side of the stack.

Rugbug,

What we are telling you is that this is a function of most print drivers.

How about you tell us what you are trying to do and what make and model printer your friend has, and why you believe this cannot be done on his/her printer.