The Quadripartite Affair

Solo blows open the ceiling vent of Illya and Marion's cell, and she stands on Illya's shoulders until Solo can reach her and pull her out. This leaves Illya with nothing/no one to stand on, no way to reach the vent and no apparent way out of the cell. But he's out just the same in the next scene, with no explanation as to how.

The Thrush guard Solo & Illya toss over the bridge railing during their escape from the compound is a little too obviously a dummy.

At the very end, in Waverly's office, the boom shadow is prominently visible on the door.

The Bow-Wow Affair

Illya takes Marion Raven's shoes off so she can climb the tree, and tosses them into the pool. But in the next shot, as she climbs, her shoes are back on. Later, when she falls into the pool, her shoes are off again, and already  floating in the water.

The Secret Sceptre Affair

Solo, Illya and Zia get out of the car and run into the woods, leaving the rear passenger-side door standing open. When they return, the door has somehow closed itself.

The Green Opal Affair

In Waverly's office, Illya hones his combat skills by swinging at a suspended wooden block with a baseball bat. When the alarm goes off, he puts the bat down on the table as he and Solo rush to the console. In the very next, reverse angle shot, the block is still swinging from the ceiling, but the baseball bat has vanished from the table.

Aboard the yacht, Solo tucks his gun into his wasteband in back. Next shot, as he takes cash out of the box, the gun is gone. It reappears in the shot after that.

The Foreign Legion Affair

Aboard the plane, Illya forgets his own secret agent number. He tells the communicator, "This is Number 2, Section 1." Illya was Number 2, Section 2. This is a little like James Bond suddenly claiming to be Agent 005.

The Hula Doll Affair

Illya stands beside the cab talking on his communicator, and the boom mike is visible over his head throughout the shot.

The Her Master's Voice Affair

When the taxi leaves the airport, it's a 1965 Ford. When next seen en route, it's suddenly a 1958 Ford with big tail fins. When it arrives at the house, it's a '65 model again.

The Yo-Ho-Ho and a Bottle of Rum Affair
The intro screen clearly says we're in Hong Kong as a ship with Illya trapped aboard steams out of the harbor. We then cut to a night shot of the ship departing what we've just been told is Hong Kong -- with a clear and unmistakable view of the Golden Gate Bridge in the background. Whups.
 

Mscl. U.N.C.L.E. Trivia:

U.N.C.L.E. stood for the United Network Command for Law & Enforcement. The original intent was that the U.N. portion of its name should stand for United Nations, until it was learned that the real U.N. doesn't permit its name to be used as part of any commercial enterprise. So the more nebulous term "Network" was used instead.

Though U.N.C.L.E. was entirely fictive, thousands of fans wrote NBC and MGM in the 60s begging to join up. Might have had something to do with the bogus disclaimer at the end of every episode: "We wish to thank the United Network Command for Law and Enforcement, without whose assistance this program would not be possible." So many requests came in that MGM printed U.N.C.L.E. membership cards and sent them to the letter writers.

Thrush, U.N.C.L.E.'s nemesis organization, was an international bad-guy conglomerate with the single-minded goal of taking over the world. Though "Thrush" was never an acronym on the show itself, U.N.C.L.E. novelist David McDaniel assigned it a meaning that became fan canon: he called it the Technological Hierarchy for the Removal of Undesirables and the Subjugation of Humanity. That pretty much described Thrush's nefarious ambitions to a T.

U.N.C.L.E. had cell phones 30 years before they were invented in the real world. Even before "Star Trek," U.N.C.L.E. had "communicators" that utilized the brand new technology of the recently launched TelStar communications satellite. The communicators were first disguised as cigarette packs and cases, but later became spiffy pocket pens that morphed into satellite radios when the cap was upended. U.N.C.L.E.'s spies then "phoned home" with the request to "Open Channel D."

"The Man From U.N.C.L.E.'s" original working title was "Solo," and its lead character was named for a spy with a minor role in one of Ian Fleming's early Bond novels. U.N.C.L.E. producer Norman Felton had a handshake agreement with Fleming to use the name and to develop "Solo" as a TV spy series. But the Bond film franchise had other ideas, reneged on the agreement on Fleming's behalf, and sued, forcing the title change. Felton prevailed only in retaining the character's name: Napoleon Solo.

To see many, many more of my Man From U.N.C.L.E. bloopers, go to:
http://www.moviemistakes.com/tv5563