The KJV is perfect - there are no errors in it. If someone has a Bible version that is not perfect, they don't have the Word of God, because the Bible itself claims to be perfect:

Psalms 19:7 The law of the LORD is perfect, converting the soul: the testimony of the LORD is sure, making wise the simple.

The word "perfect" means complete - but it also has the idea of without blemish, without spot:

The word used for perfect in the verse above is:

from 8552; entire (literally, figuratively or morally); also (as noun) integrity, truth:--without blemish, complete, full, perfect, sincerely (-ity), sound, without spot, undefiled, upright(-ly), whole.

1 Corinthians 13:10 But when that which is perfect is come, then that which is in part shall be done away.

James 1:25 But whoso looketh into the perfect law of liberty, and continueth therein, he being not a forgetful hearer, but a doer of the work, this man shall be blessed in his deed.

from 5056; complete (in various applications of labor, growth, mental and moral character, etc.); neuter (as noun, with 3588) completeness.

The King James Bible is perfect. It is without errors or contradictions.