This is network generated error. Please find the below steps to resolve the above error:

 

1) Please check the sleep mode settings on server machine, kindly set the sleep mode as " Never ".

 

2) Please check the network connectivity between client and server.

 

3) Please check the SQL services, kindly restart the SQL services. Please find the below screenshot for the same.

 

Windows Start>>Search: " Services "



Once you follow above mentioned steps on Client -Server Machines, It will resolve this error.