On Thursday, Sen. Richard Burr (R-N.C.) became the latest politician to get tripped up by stock images. Burr, who is in an increasingly close reelection bid, released an ad of a pastor praising the two-term senator for working with disadvantaged children.

"He is genuinely interested in our community, in our children," Pastor Kirby Jones of Raleigh says in the ad.

The video cuts to a lovely shot of uniformed children in a classroom, focused and scribbling on their papers. The message is clear: Burr is a politician the state's growing African American community can trust.

Except the children in the picture aren't from North Carolina. Or anywhere close to it.

A quick Google Image search shows these children can be found in two separate Getty Image stock videos marked "Africa" or "Non-US Location." (It also says "African American Ethnicity," which could be how the videographer found it, since these videos are largely categorized and found by keywords.)

Lauren Fox with Talking Points Memo first caught the trip-up. The ad's maker, Doug McAuliffe, told Fox the team used stock footage because it didn't want to politicize Pastor Kirby's students and potentially jeopardize its nonprofit status.

Burr's campaign told Fox this was much ado about nothing; it was his Democratic opponent Deborah Ross stirring up trouble.

But this was also a needless mistake at a time when Burr can't afford to make too many. Monmouth University and CNN/ORC polls released this week suggested the race is within the margin of error despite a majority of the electorate not having an opinion of Ross, suggesting she could be within reach with Hillary Clinton's coattails.

Of course, Ross herself recently weathered some criticism after her first TV ad of testimonials from voters used at least four stock photos of models instead of North Carolina residents.

In fact, the stock image "oops" is a time-honored trail tradition. Since it happens so often, we thought it time to put together a quick "do" and "don't" reminder checklist, based on this year's slip-ups.

Don't: Use photos of anything resembling Nazis in any way, shape or form.

Donald Trump tweeted in July a stock photo of actors re-enacting World War II, wearing Nazi uniforms. He deleted it, blaming "an intern."

Do: Check if your featured actor has worked in porn.

In February, Ted Cruz ran an attack ad against Marco Rubio titled "Conservatives Anonymous," a group-therapy session of voters struggling to reconcile their support for Rubio.

An actress who got hired for the ad had appeared in several porn movies (in addition to "Star Trek: Voyager.") Cruz's campaign pulled the ad.

"It happened that one of the actresses who was there had a more colorful film history than we were aware," Cruz told reporters. "We would not have cast her had we known of that history."

Do: Make sure stock footage was shot in America.

An ad by a Jeb Bush super PAC used footage of the sun rising over a field in Britain and of a construction worker in Southeast Asia to try to show the "brighter path" Bush would lead the country on.

A Rubio ad tried to riff off Ronald Reagan's classic "Morning Again," but showed a boat crossing a harbor in what appears to be Vancouver, Canada.