Hillary Clinton decides to send Donald Trump a letter to let him know how she feels about him. 
Trump opens the letter and it appears to contain a single-line coded message: 370HSSV 0773H. 
Trump, not for the first or last time, is completely baffled, so he emails it to Melania Trump and his children. 
They have no clue either, so he sends it to the FBI. 
No one can solve it at the FBI, CIA or NASA. 
They eventually ask Britain’s MI6 for help. Within minutes, MI6 cables the reply: ‘‘Tell Mr Trump that he is holding the message upside down.’’
Please be careful if you are going to stand on your head to view your monitor upside down!