The SetKeepAliveTime method is used to set how often TCP attempts to verify that an idle connection is still available by ...

The SetKeepAliveTime method is used to set how often TCP attempts to verify that an idle connection is still available by sending a Keep Alive packet. If the remote system is still reachable and functioning, it will acknowledge the Keep Alive transmission. Keep Alive packets are not sent by default. This feature may be enabled in a connection by an application. The method returns an integer value that can be interpretted as follows:  0 - Successful completion, no reboot required 1 - Successful completion, reboot required 64 - Method not supported on this platform 65 - Unknown failure 66 - Invalid subnet mask 67 - An error occurred while processing an Instance that was returned 68 - Invalid input parameter 69 - More than 5 gateways specified 70 - Invalid IP  address 71 - Invalid gateway IP address 72 - An error occurred while accessing the Registry for the requested information 73 - Invalid domain name 74 - Invalid host name 75 - No primary/secondary WINS server defined 76 - Invalid file 77 - Invalid system path 78 - File copy failed 79 - Invalid security parameter 80 - Unable to configure TCP/IP service 81 - Unable to configure DHCP service 82 - Unable to renew DHCP lease 83 - Unable to release DHCP lease 84 - IP not enabled on adapter 85 - IPX not enabled on adapter 86 - Frame/network number bounds error 87 - Invalid frame type 88 - Invalid network number 89 - Duplicate network number 90 - Parameter out of bounds 91 - Access denied 92 - Out of memory 93 - Already exists 94 - Path, file or object not found 95 - Unable to notify service 96 - Unable to notify DNS service 97 - Interface not configurable 98 - Not all DHCP leases could be released/renewed 100 - DHCP not enabled on adapter Other - For integer values other than those listed above, refer to Win32 error code documentation.