Nokia Lumia after Windows 8.1 update does not sync contacts with Whatsapp

[WPCentral Question]

Nokia Lumia after Windows 8.1 update does not sync contacts with Whatsapp . I have 6.000 contacts in Google Mail and Hotmail, help please .
Also Windows Outlook does not sync properly .

 

[dem-net]

I have the same problem !!!
Have you tried to restore the OS to factory settings?