I can login on linux workstation but the icons or generally ... the windows are different

This could happen when:

• you have logged in (in graphical mode) in another workstation of your Sector with different software versions (op. system or/and window manager versions), please read the page: DO NOT USE two or more linux workstations in " graphical mode " (local connection) simultaneously or use another linux workstation (not the workstation assigned to you) in " graphical mode ".
  

You have to clean some directories and files on your main directory.
Ask help to helpdesk staff.