Saying Bismillah at wudu

It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "There is no prayer for the one who has no ablution, and there is no ablution for the one who did not mention the name of Allah (at its start)."

It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "There is no prayer for the one who has no ablution, and there is no ablution for the one who did not mention the name of Allah."
This hadith has a sahih (authentic) chain, and Imam Muslim used Ya'qub bin Abi Salamah as evidence, but the two Shaykhs did not record it; and it also has a supporting report (shahid).

It is narrated from Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "There is no prayer for the one who has no ablution, and there is no ablution for the one who did not mention the name of Allah (at the start of ablution)."

Ali bin Bundar al-Zahid informed us; he said: Umar bin Muhammad bin Jubayr narrated to us; he said: Abu Bakr al-Athram narrated to us; he said: I heard Imam Ahmad bin Hanbal when he was asked about a person who performs ablution without mentioning the name of Allah (Bismillah). Imam Ahmad said: The best that is narrated on this matter is the narration of Kathir bin Zayd.