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How can I solve an error "10048 (Address already in use.)" in Webserver Stress Tool?



In Webserver Stress Tool, I get an error message # 10048 Address already in use. Where does it come from and how can I solve this issue?

error networking registry webserver-stress-tool

Created on Feb 24, 2010 9:05:50 AM by  Daniel Zobel [Product Manager]

Last change on Jul 21, 2010 1:54:37 PM by  Daniel Zobel [Product Manager]

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Accepted Answer



Avoiding "10048 (Address already in use.)" Errors in Webserver Stress Tool

For high traffic scenarios this message shows a problem on the workstation running Webserver Stress Tool. The IP stack can't create additional outgoing TCP/IP connections because it runs out of available socket numbers for the IP address(es) that you have configured in Webstress.

This error occurs when your workstation cannot allocate new sockets. On Windows the default limitation is 5000 - 1024 open sockets (5000 is the default max user port setting and the first 1024 ports are reserved).

You can increase the default maximum socket value in the registry:


and add or modify the MaxUserPort value.

See Also

Created on Feb 24, 2010 9:10:15 AM by  Daniel Zobel [Product Manager]

Last change on Sep 1, 2015 8:07:43 AM by  Erhard Mikulik [Paessler Support]

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.