#Inital user and passw need to be defined up here
log=False
while log==False: #to loop until a correct password is aqquired
    try:
        server.login(user, passw) #attempt to log into smtp server
        log=True #sets to true if log in is successful
    except:
        print('Incorrect Username or Password:n')
        user=input('Enter new Username: ') #gets new username and password
        passw=input('Enter new Password: ')