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Take into account that when executing WMI scans on large IP ranges, a No buffer available space exception may occur since the scan depends on available TCP ports. 

Dynamic Port Range is used by the client computers (or a server acting as a client) to connect to Well Known Port Services or Root Services. A DNS Server is acting as a Server and listening on a specific Well Known Port (Port TCP and UDP 53). The Dynamic Port Range used by the client computers depend on the version of Operating Systems.

Port Range: 1024-65535

This port range is used by the computers running Windows XP, Windows 2000 Professional, and Windows Server 2003. A client computer running this version will always pick a port from the above mentioned Dynamic Port Range.

Port Range: 49152-65535

The Dynamic Port Range has been changed in the Windows Vista, Windows 7 and Windows Server 2008. By default, a fresh Windows Server 2008 installation will have this Dynamic Port Range configured. To see the port range, you can use the following commands:

    NetSh INT IPV4 Show DynamicPort TCP
    NetSh INT IPV4 Show DynamicPort UDP

To set or change the Dynamic Port Range:

    NetSh INT IPV4 SET DynamicPort TCP Start=1024 num=65535
    NetSh INT IPV4 SET DynamicPort UDP Start=1024 num=65535


if we found this type of error then we can fix via following steps

A) check dynamic port range using NetSh INT IPV4 Show DynamicPort TCP
b) If number of port less then with combination of IP from given IP range we can increase port like NetSh INT IPV4 SET DynamicPort TCP Start=1024 num=65535
c) run scan again, it will find more instanse


Here is more wayt to Increase the range of ephemeral ports
Windows 2003

Increase the range of ephemeral ports by setting the MaxUserPort TCP/IP parameter to an higher value (like 32768), on the windows registry key HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters, as a DWORD value. This will set the port range from 1024 to 32768.

Windows 2008 R2


Increase the range of ephemeral ports by setting the dynamicportrange to an higher value through the command netsh int ipv4 set dynamicportrange tcp start=32767 num=65535, this will set the port range from 32768 to 65535.

Redhat LInux 5

Increase the range of ephemeral ports by setting ip_local_port_range kernel value on /proc/sys/net/ipv4/ip_local_port_range, using the command echo "32768 65535" > /proc/sys/net/ipv4/ip_local_port_range, this will set the port range from 32768 to 65535.