When pictures showing Prince William as a regular person were posted on the royal couple's new website, they appeared to just show him at work.
But in the background was sensitive information including usernames and passwords on computer screens that could have lead to a major security breach.
"A number of photographs of Flight Lieutenant Wales were taken whilst on duty working as a helicopter search and rescue pilot," said a defence spokesman in a statement. "Due to an administrative oversight, these photographs were not properly cleared at RAF Valley. The passwords and user names shown have now been reset as a precaution and we are satisfied the images do no contravene security regulations."
[ Related photos: Prince William hard at work ]
The images were taken by a Ministry of Defence photographer and were quickly taken down from the couple's official site, but not before they appeared on news websites, such as the Guardian.
The images were part of a royal PR initiative to show him as a search and rescue pilot and publicize the new official website for the royal couple. They are carefully crafted and try to show the Duke and Duchess as "working royals."
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They showed him sitting at a computer, getting tea, making his bed and attending a briefing. They were replaced a short time later with similar images that have the information blurred. The ministry requested media outlets use the new versions of the photos.
According to the Guardian, a St. James's Palace spokeswoman said four photos had been replaced and the pictures were supplied by RAF Valley so it was a ministry issue.
William's tasks as a pilot include checking the airframe, fuel, hydraulic and navigation systems, according to The Sun.
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"It's rewarding because every day you come in to work you don't quite know what's going to happen. It's quite exciting in that sense, it's unpredictable," said Will of his job last April. "But at the same time, it's great that you get to go out and actually save someone's life hopefully or at least make a difference to somebody. When you know that they are in trouble, you do everything you can to get there."
For accidentally showing sensitive information, St. James's Palace and the U.K. Ministry of Defence are both awarded this week's Gaffe of the Week. We commemorated this with a statue of Rob Ford in butter.
Gaffe of the Week runs each Thursday on Yahoo! Canada News.
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