The 28-year-old royal, who is preparing to marry Jack Brooksbank on 12 October, shared a picture of her “Papa” to her 288,000 Instagram followers in June.
Speaking to British Vogue, Eugenie explained how the social media post, which received nearly 50,000 likes, landed her in hot water with the palace.
“I recently got in trouble for posting a picture of Papa in a corridor of the palace that was off-limits to the public,” she said.
Prince Andrew, 58, happily smiles in the picture, wearing his redcoat military uniform from his first Trooping of the Colour ceremony as Colonel of the Grenadier Guards to mark the Queen’s 92nd birthday.
The private corridor he stands in is complete with a red carpet and numerous paintings, including one of Princess Maud of Wales’ wedding, and a line of marble head sculptures.
Eugenie’s comments were part of her first joint interview with older sister Princess Beatrice for the September issue of the fashion magazine.
The younger daughter of Prince Andrew and Sarah, Duchess of York, also revealed details about her upcoming wedding, claiming it will be plastic-free.
“My whole house is anti-plastic now – and Jack and I want our wedding to be like that as well,” she said.
Eugenie recently became an ambassador for Project O, which in partnership with Sky Ocean Rescue aims to restore and protect the ocean.
Following the lead of her cousin Prince Harry and his new wife Meghan, Duchess of Sussex, Eugenie will wed at St George’s Chapel in Windsor Castle.
The young royal has been dating Mr Brooksbank, 31, for seven years. The couple were first introduced by friends on a ski break in Verbier, Switzerland.
Mr Brooksbank proposed in Nicaragua when the couple were on holiday and had asked Prince Andrew for his permission beforehand.
Despite her wedding excitement, Eugenie admitted it’s “very nerve-wracking because you want it to be perfect”.