Is seeing God Almighty in a dream permissible or not?

Seeing Allah Almighty in this world while awake is not possible. The proof for this is Allah Almighty's statement to Musa (peace be upon him): "You will not see Me," and the Prophet's (peace and blessings of Allah be upon him) statement: "I saw a light" when he was asked if he had seen his Lord. Allah is veiled by light, and if He were to remove it, the effulgence of His Face would incinerate everything His gaze reached of His creation.

As for dreams, the Prophet (peace and blessings of Allah be upon him) saw his Lord. Scholars have differed on the possibility of others seeing Allah in a dream. It is preferable to close this door to prevent the opening of doors to superstitions and false claims.