One user has access to internet and the other 2 do not??

[Woo W]

My laptop ( Windows7 ) has 3 different users aka me and my family. Everything works fine until few days ago 2 of the 3 users cannot access to internet. Both of the users successfully connected and have good signal but everytime I launch any internet required program it says DNS error. And on the other side the 3rd user has no issues at all. Any ideas of what is happening to my laptop? Thanks in advance.

 

[CrispyPata]

Try to flush DNS

Go to Command Prompt, press Win + R and type cmd .
Type ipconfig /flushdns . Wait for the command to process and then restart your computer.
Test the connection.