She wore the burqa’ (face veil) when in ihraam and she did not know that it is haraam
Question

                Is it permissible for a woman to wear the burqa’ (a kind of face veil) when in ihraam? My family wore it and when they came back from Hajj they were told that their Hajj was not acceptable, because they wore the burqa’.
Praise be to Allah.
    Wearing the burqa’ is not permissible for a woman in ihraam, 
    because the Prophet  (peace and blessings of Allaah be upon him) said: 
    “Women should not wear niqaab or gloves.” Narrated by al-Bukhaari. But there 
    is no sin on a woman who wears the burqa’ in ihraam because she is unaware 
    of the prohibition, and her Hajj is valid. 

    And Allaah is the Source of strength. May Allaah send 
    blessings and peace upon our Prophet Muhammad and his family and companions. 
    End quote. 

    Standing Committee for Academic Research and Issuing Fatwas 

    Shaykh ‘Abd al-‘Azeez ibn ‘Abd-Allaah ibn Baaz, Shaykh ‘Abd 
    al-Razzaaq ‘Afeefi, Shaykh ‘Abd-Allaah ibn Qa’ood.