To believe that the months of Muharram and Safar bring misfortune or calamity or that a marriage performed in these months will be negatively affected is an un-Islamic belief. The Noble Qur'an states: "No calamity (or harm) can occur, except by the will of Allah". (Surah 64 - Verse 11).
Hazrat Abu Hurairah (R) narrates that Rasulullah (Sallallahu Alahi Wasallam) said, “…There is no bad omen in the month of Safar” (Bukhari)
To marry during the months of Muharram, Safar or any other month of the year is allowed as Islam has placed no restrictions in this regard. We should reaffirm our belief and conviction that benefit and harm is from Allah Ta'ala alone and occur with his knowledge and permission. No time or person brings bad luck or ill fate.
In order to draw from the protection and mercy of Allah Ta'ala, we should develop the capacity to perform actions that prevent calamities and misfortunes such as performing our five daily Salah, making daily Dua for goodness and protection, seeking forgiveness, repentance, abandoning sins and vices, improve our conduct and give regular charity.