Printing to an LPR port is unsuccessful and printer ports are missing

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256986 Description of the Microsoft Windows registry


When you try to print to a printer by using a line print remote (LPR) port, the job may not be printed. When you view the printer properties and examine the list of ports, some or all the printer ports may be missing.


This problem can occur when an LPR port is corrupted.


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To resolve this issue, use one or more of the following methods to determine which LPR port is corrupted. Then, delete the corrupted port.

Method 1

Try to locate and delete the corrupted LPR port.

Note The last port that is listed in Print Manager may give you an idea of where to look for the corrupted port.
  1. Start Registry Editor (Regedt32).
  2. Make a backup of the following LPR port registry key so that when you determine which port is corrupted, you can restore the key and just delete the corrupted port.
  3. Look for a corrupted port name in this registry key.
  4. If you locate a corrupted port name, delete the port.
  5. Quit Registry Editor.

Method 2

If you cannot identify a corrupted port name, or if no ports are listed, try to identify the corrupted port by deleting the ports one at a time, stopping and restarting the spooler every time to see whether the ports reappear. After you identify the corrupted port, restore the LPR port registry key that you backed up and saved, and then delete the corrupted port.

Method 3

If you still cannot identify the corrupted port, verify the validity of the ports that the printers are configured to print to. To do this, follow these steps:
  1. Start Registry Editor.
  2. Locate the following registry key:
  3. Verify that the printers are configured to print to a valid LPR port, not to a universal naming convention (UNC) print share name such as \\server_name\printer_share. If a printer is configured to print to a UNC share name, and you can determine which LPR port the printer is supposed to print to, that LPR port may be the cause of the problem.
  4. Quit Registry Editor.

Method 4

If you cannot identify the corrupted LPR port, delete all the LPR ports. Then, re-create them manually in Print Manager.

Artikelnummer: 250209 – Letzte Überarbeitung: 31.10.2006 – Revision: 1