Hi Beata,

Try the steps in the following order to resolve your problem:

• Press Windows Key + R to open Run window. Inside Run window, type cmd (select the one with administrator privilege)
• netsh int ip reset c:\resetlog.txt   : This is going to reset ip
• netsh winsock reset  : This command is used to reset winsock. Although resetting winsock is not related to this error, it might help in fixing other problems which can lead to this error. Once the command is executed, it will create a prompt to restart. Do not restart now. This will help reset winsock settings.
• ipconfig /flushdns : This command help in flushing the stored DNS cache.
• Restart Laptop and check if the issue is fixed.

• Do a power cycle of modem and Laptop.
  Turn off your Laptop and then turn off the modem and router (if present). Keep it turned off for 5minutes. The power is turned off for 5minutes to make sure the power is drained out completely and ensure proper reset of settings.
• Now turn it on and check if the problem is fixed.

• Press Windows Key + R. In the run window, type ncpa.cpl. This will open network connections
• Right click Local area connection, then click properties. (If it is wireless connection, right click on Wireless Network Connection)
• Select Internet protocol version(TCP/IPv4), then click properties
• Select internet protocol ,select “use the following DNS server address”
• change DNS server address to global DNS value given below
  Preferred 208.67.222.222
  Alternate 208.67.220.220 (You can also use Google’s DNS address preferred 8.8.8.8 and alternate 8.8.4.4)
• Check if issue is fixed. Changing the Preferred and Alternate error usually fix most of the cases.