Windows 95 users will require Winsock2 to be installed on their system before using Port Explorer. Winsock 2 can be downloaded from Microsoft at this URL:
http://www.microsoft.com/windows95/downloads/contents/wuadmintools/s_wunetworkingtools/w95sockets2/default.asp

Limitations: Windows 95 users will not be able to use the View Statistics feature as this information is not provided by the operating system. The "Kill Socket" feature is also unavailable under Windows 95 as this technique is not supported by the operating system.

Windows NT4

Windows NT4 users will require at least NT4 Service Pack 4 (or later) installed. More information can be obtained from Microsoft at this URL:
http://support.microsoft.com/default.aspx?scid=FH;[LN];ntw40

Windows NT4/2K/XP/2003

Under Windows 95/98 Port Explorer isn't able to map all sockets to their parent process (usually only the ones that are loaded very early by the system). Such processes will normally display with the process name of "--NETSTAT--", indicating that Port Explorer wasn't able to map the process, but it could still see the socket using standard netstat techniques. However, under Windows NT4, 2K, XP and 2003, Port Explorer is able to map ports to all processes by using undocumented functions that are built into the operating system. Sockets that would normally display as '--NETSTAT--' but have been resolved by Port Explorer using this technique will have an asterisk beside their name, for example:
 * c:\path\process.exe
 rather than...
  c:\path\process.exe

Windows XP/2003

In some rare circumstance, Windows XP doesn't clean up all its sockets correctly after an application has closed. This has the effect of Port Explorer showing a socket with an asterix and no filename because the application is closed yet Windows XP is reporting that the closed application owns the socket(s). Usually after your internet connection has been disconnected the 'blank' socket(s) will be cleaned up by Windows XP. This isn't a Port Explorer problem, it's a Windows XP issue. To check this, whenever you see a blank socket go to your command prompt and type "netstat -ano" (without quotes). You should see the sockets which have the same PID as the blank sockets in Port Explorer. If you look in Windows Task Manager (Ctrl+Alt+Delete | Task Manager) you will see no process that has the PID that netstat and Port Explorer report.