The five-year-old went off at 8-13 to make it a hat-trick of victories in the Arc, but a disappointing performance saw the filly fade away in the final furlong to finish second.
Waldgeist swooped past with ease to land the €3,150,000 ($3,456,340) prize at odds of 16-1.
Enable wasn't the only disappointment at Longchamp, as odds-on favourite Battaash finished 14th out of 16 in the Longines, failing to cope with the soft ground and rounding off a frustrating day for favourite backers.
Media Relations at William Hill, Rupert Adams, said the operator breathed a sigh of relief after suffering a tough weekend.
He told Gambling Insider: "Clearly the Enable result was a thing for the industry and was very much needed after a terrible Saturday at Ascot when five favorites won in a row.
"That said, Enable was 8-13 and therefore a very short price, so it was the doubles and trebles with Battaash and Mehdaayih we were worried about. However, all three lost."
Sky Bet Head of Sports PR Michael Shinners also told Gambling Insider: "Despite UK runners featuring prominently in the betting across Sunday’s Longchamp card, the day predictably hinged solely around Enable in the feature.
"The lure of four places in an attractive ach Way race couldn’t persuade the majority of our customers to desert the star mare and we saw in excess of 75% of bets placed on the favourite, inclusive of out Price Boost market. Needless to say her defeat was an excellent result in our books."
