googled:
The denial of the style Her Royal Highness to the Duchess of Windsor caused conflict, as did the financial settlement—the Government declined to include the Duke or the Duchess on the Civil List, and the Duke's allowance was paid personally by the King. But the Duke had compromised his position with the King by concealing the extent of his financial worth when they informally agreed on the amount of the sinecure the King would pay. Edward's wealth had accumulated from the revenues of the Duchy of Cornwall paid to him as Prince of Wales and ordinarily at the disposal of an incoming king. The new King and Queen also paid Edward for Sandringham House and Balmoral Castle. These properties were Edward's personal property, inherited from his father, King George V, and thus did not automatically pass to George VI on his accession. Relations between the Duke of Windsor and the rest of the Royal Family were strained for decades.