You are using a computer that is running Windows Vista, Windows Server 2003, or Windows XP.
You try to print to a Line Printer Remote (LPR) printer by using LPR port monitor software or TCP/IP port monitor software.
In this scenario, you experience slow printing performance.
This problem occurs because some printers use delayed acknowledgement (ACK) algorithms to decrease TCP overhead. A delayed ACK of up to 200 milliseconds may occur if a printer that uses these algorithms receives an odd number of packets from a computer that sends print jobs to the printer. During this 200-millisecond delay, the computer waits to send additional data to the printer. These 200-millisecond delays accumulate over time, and they eventually cause a significant reduction in the overall transfer speed of the print job.
Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756 How to back up and restore the registry in Windows
To work around this problem, increase the size of the default Winsock send buffer, and then use the LPR port monitor to send the print job. To increase the size of the buffer, follow these steps.
Click Start, click Run, type regedit, and then click OK.
Locate and then click the following registry subkey:
Windows Vista Enterprise 64-bit Edition, Windows Vista Home Basic 64-bit Edition, Windows Vista Home Premium 64-bit Edition, Windows Vista Ultimate 64-bit Edition, Windows Vista Business, Windows Vista Business 64-bit Edition, Windows Vista Enterprise, Windows Vista Home Basic, Windows Vista Home Premium, Windows Vista Starter, Windows Vista Ultimate, Microsoft Windows XP Home Edition, Microsoft Windows XP Professional, Microsoft Windows Server 2003, Datacenter Edition (32-bit x86), Microsoft Windows Server 2003, Datacenter Edition for Itanium-Based Systems, Microsoft Windows Server 2003, Datacenter x64 Edition, Microsoft Windows Server 2003, Enterprise x64 Edition, Microsoft Windows Server 2003, Enterprise Edition (32-bit x86), Microsoft Windows Server 2003, Enterprise Edition for Itanium-based Systems, Microsoft Windows Server 2003, Standard x64 Edition, Microsoft Windows Server 2003, Standard Edition (32-bit x86)