Windows Sometimes the server crashes at certain point

When i got this warning message, all players have kicked. No idea why

# OS
Windows 7 Ultimate K (Korea)

# Server Specs
Processor: 1 * AMD Neo 1.3gHz
Processor cores available: 2 cores
Memory: 8 Gb
Network controller: 1GbE NC107i 1 Port
Storage: 1 * 64 Gb SSD

# Router Spec
CPU: 384MHz MIPS 32bit
** This router can't support ipv6
** 50301(tcp/udp) port was foward to my server

# autoconfig.cfg
sv_gamemode = Zombies_v1.05
sv_mapcycle =
sv_gravity = 9.81
sv_canpause = 1
sv_test = 0
sv_restart_on_update = 1
v_showminimap = 1
security_whitelist_active = 0
security_whitelist = ../Security/whitelist.cfg
security_blacklist = ../Security/blacklist.cfg
security_ignorelist = ../Security/ignorelist.cfg
security_seclevs = ../Security/seclevs.cfg
sv_maxplayers = 8
sv_enable_joinfull = 1
sv_reservedslots = 0
sv_ip = 0
sv_ipv6 = 0
sv_register = 1
sv_preferAF = 0
sv_enableIPv6 = 1
sv_port = 50301
cl_port = 50328
sv_password =
sv_rconpassword =
disable_seclevoutput = 1
sv_allow_globals_mods = 1
sv_compression = 1
sv_maxping = 450
sv_maxping_warnings = 600
sv_maxhack_warnings = 25
sv_name = MYSERVERNAME
sv_info =
sv_global_bans = 0
u_shownames = 0
sv_tcpr = 0

 

Turn it off and on again? In other words has this happened more than once or twice?

 

No.. Server did not turn off. But this happened still occurs. all player kicked.