A method for ensuring reliable communication between a security software client and cloud includes detecting whether communication between the security software client and the cloud is abnormal; determining whether network configuration is abnormal if the communication between the security software client and the cloud is abnormal; restoring the network configuration into default network configuration if the network configuration is abnormal, wherein the default network configuration is system configuration used when the communication between the security software client and the cloud is normal; determining whether the communication between the security software client and the cloud is abnormal after the network configuration is restored into the default network configuration; and prompting a user that the communication between the security software client and the cloud is abnormal if the communication between the security software client and the cloud is abnormal after the network configuration is restored into the default network configuration.