The Dead Sea Scrolls have all of the books of the OLD Testament except for Esther and Nehemiah and we also know that the Bible was not corrupted when Mohammad was around.

Because

The Quran affirms that the Bible is the word of God.

Yes. You read that correctly. When one begins to examine the Quranic narrative, he or she will quickly come to discover that the Quran affirms the bible’s divine inspiration and inerrancy. Many Muslims, however, assert that such passages are referring to the “REAL” bible.

In other words, prior to its supposed corruption. Yet when we read the following verses, it becomes blatantly clear that “Allah” and his prophet considered the bible to be uncorrupted and inspired DURING THE TIME OF MUHAMMAD:

Surah 5:43: “But why do they come to thee for decision, WHEN THEY HAVE (THEIR OWN) TORAH BEFORE THEM? THEREIN IS THE (PLAIN) COMMAND OF ALLAH; yet even after that, they would turn away. For they are not (really) People of Faith.

Surah 5:46-47: “And in their footsteps We sent Jesus the son of Mary, CONFIRMING THE TORAH THAT CAME BEFORE HIM: We sent him the Gospel: THEREIN IS GUIDANCE AND LIGHT, and confirmation of the torah that had come before him: a guidance and an admonition to those who fear Allah. LET THE PEOPLE OF THE GOSPEL JUDGE BY WHAT ALLAH HATH REVEALED THEREIN. IF ANY DO FAIL TO JUDGE BY (THE LIGHT OF) WHAT ALLAH HATH REVEALED, THEY ARE (NO BETTER THAN) THOSE WHO REBEL.”

Sunan Abu Dawud, Book 38 (Kitab al Hudud, i.e. Prescribed Punishments), Number 4434: Narrated Abdullah Ibn Umar: A group of Jews came and invited the Apostle of Allah (peace_be_upon_him) to Quff. So he visited them in their school.They said: AbulQasim, one of our men has committed fornication with a woman; so pronounce judgment upon them. They placed a cushion for the Apostle of Allah (peace_be_upon_him) who sat on it and said: Bring the Torah. It was then brought. HE THEN WITHDREW THE CUSHION FROM BENEATH HIM AND PLACED THE TORAH ON IT SAYING: I BELIEVED IN THEE AND IN HIM WHO REVEALED THEE.

Here are some things to note:

In surah 5:43, the Jews HAVE the Torah (Present tense). THEREIN IS Allah’s command.
In surah 5:46-47 it writes THEREIN IS GUIDANCE. Furthermore, Allah instructs us to JUDGE (Present tense) by the gospel.
Muhammad considered the Torah that existed in HIS time to be the word of God.

Now in light of the Islamic evidence, a segment of the Muslim community have conjured up a theory that the bible was corrupted AFTER Muhammad’s time. This is simply impossible, seeing as we have manuscripts of the bible which date back prior to and during Muhammad’s time.

In other words, we know exactly what the bible said during the commencement and launch of the Islamic religion:

The Chester Beatty Papyrus II: AD 100.
The John Rylands Manuscript: AD 130.
The Codex Vaticanus: AD 325- 350.
The Codex Sinaiticus: AD 375-400.
The Codex Washingtonianus: AD 450.

Since we know the Bible was not corrupted by referring to these ancient documents and papyri, we see that Islam is proven to be locked into a grave dilemma. If the bible was corrupted, then the Quran is false because it affirms its inerrancy and inspiration. But if the bible was NOT corrupted, the Quran STILL remains false because it blatantly contradicts the biblical narrative on virtually every significant point.