networking - Ping Result:General Failure When disconnect from vpn

In Windows 8 When i connecte to the vpn and then disconnect from it, i get general failure.

PING: transmit failed. General failure.

the routing table are:

Network Destination        Netmask          Gateway       Interface  Metric
0.0.0.0                   0.0.0.0    192.168.137.1   192.168.137.86     30

But it won't work, but when i add two other routing route it will work successfully:

Network Destination        Netmask          Gateway       Interface  Metric
128.0.0.0                 128.0.0.0    192.168.137.1   192.168.137.86     30
0.0.0.0                   128.0.0.0    192.168.137.1   192.168.137.86     30

what is the problem?