The word(s) "err" appears 106 time(s) in 99 verse(s) in Quran in Muhammad Pickthal translation.

(11) Seest thou not those unto whom a portion of the Scripture hath been given, how they purchase error, and seek to make you (Muslims) err from the right way?

(12) And if any tidings, whether of safety or fear, come unto them, they noise it abroad, whereas if they had referred it to the messenger and to such of them as are in authority, those among them who are able to think out the matter would have known it. If it had not been for the grace of Allah upon you and His mercy ye would have followed Satan, save a few (of you).

(13) Those of the believers who sit still, other than those who have a (disabling) hurt, are not on an equality with those who strive in the way of Allah with their wealth and lives. Allah hath conferred on those who strive with their wealth and lives a rank above the sedentary. Unto each Allah hath promised good, but He hath bestowed on those who strive a great reward above the sedentary;

(14) They ask thee for a pronouncement. Say: Allah hath pronounced for you concerning distant kindred. If a man die childless and he have a sister, hers is half the heritage, and he would have inherited from her had she died childless. And if there be two sisters, then theirs are two-thirds of the heritage, and if they be brethren, men and women, unto the male is the equivalent of the share of two females. Allah expoundeth unto you, so that ye err not. Allah is Knower of all things.

(15) O ye who believe! Profane not Allah's monuments nor the Sacred Month nor the offerings nor the garlands, nor those repairing to the Sacred House, seeking the grace and pleasure of their Lord. But when ye have left the sacred territory, then go hunting (if ye will). And let not your hatred of a folk who (once) stopped your going to the inviolable place of worship seduce you to transgress; but help ye one another unto righteousness and pious duty. Help not one another unto sin and transgression, but keep your duty to Allah. Lo! Allah is severe in punishment.

(16) Say: O People of the Scripture! Stress not in your religion other than the truth, and follow not the vain desires of folk who erred of old and led many astray, and erred from a plain road.

(17) O ye who believe! Ye have charge of your own souls. He who erreth cannot injure you if ye are rightly guided. Unto Allah ye will all return; and then He will inform you of what ye used to do.

(18) (Remember) when Abraham said unto his father Azar: Takest thou idols for gods? Lo! I see thee and thy folk in error manifest.

(19) Lo! thy Lord, He knoweth best who erreth from His way; and He knoweth best (who are) the rightly guided.

(20) How many a township have We destroyed! As a raid by night, or while they slept at noon, Our terror came unto them.