Undertakers hired to transport the Queen's coffin from Balmoral removed a large sticker advertising their firm from the hearse's window while en route.
The ad for William Purves was visible as the cortege set off for Edinburgh from the Highland retreat this morning but it had vanished when they arrived at the Palace of Holyroodhouse.
The sticker obscured the monarch's oak coffin which was draped in the Royal Standard of Scotland flag.
The procession of vehicles stopped at least once during the six-hour journey to allow the drivers to rest.
It is likely the advert was then spotted and peeled off - though not before the firm's website crashed, presumably due to scores of TV viewers trying to access it.
An error message appeared for some time after the hearse first appeared around 10am.
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Later, when it was live again, a message on the homepage said: "When you place your trust in William Purves you can expect the highest standards of professionalism, compassionate care and a truly distinct service.
"Whatever you need, whatever your plans, lean on our experience, wherever and whenever you need us."
The funeral directors were selected by the Lord Chamberlain's Office.
The Scottish-based firm was hired for the first leg of the Queen's final journey.
Grieving children Prince Andrew, Prince Edward and Princess Anne lined up to greet her coffin.
Crowds gathered in the city to pay their respects at the Palace.
The coffin will rest in the throne room until tomorrow afternoon.
It will then travel in a procession to Edinburgh's St Giles' Cathedral, along the Royal Mile, with the King and the late Queen's other children the Princess Royal, the Duke of York and the Earl of Wessex following behind on foot, along with Anne's husband Admiral Sir Tim Laurence.
Camilla, now Queen Consort, and the Countess of Wessex will follow by car and also attend the service in St Giles'.
Mourners will be able to view the coffin from 5pm, City of Edinburgh Council have confirmed.
The Queen will lie in state at St Giles Cathedral on Edinburgh’s High Street for 24 hours and members of the royal family, including the King, will stand beside the coffin from 7.20pm in a tradition known as the Vigil of the Princes.
The Princess Royal will accompany the Queen's body back to London on Tuesday, September 13 on an RAF flight.
* This weekend, the Daily Mirror and Sunday Mirror celebrate the life of Her Majesty the Queen with a commemorative special filled with all the key moments from Britain’s longest reigning monarch.
Be sure to pick up your copy of the Daily Mirror and Sunday Mirror to get both pullouts.