Tahiyyat-ul-Masjid being offered when entering any Masjid

A: It is permissible for whomever enters the Masjid at times, other than that when prayers are not forbidden, to offer two Rak`ahs (units) of tahiyyat-ul-Masjid (two-unit-Prayer to greet the mosque) whether they entered to offer Salah, attend a lesson, or for other purposes before they sit. Furthermore, they must perform Wudu' (ablution) before offering Tahiyyat-ul-Masjid. As for the times in which Salah is forbidden - after `Asr (Afternoon) prayer until sunset and after Fajr (Dawn) Prayer to twenty minutes after sunrise - it is permissible to offer two Rak`ahs of Tahiyyat-ul-Masjid in accordance with the Hadith which indicate such permissibility.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.