I guess their system doesn't like it.[http://www.shure.com/idc/groups/tech_pubs/@global_managed/documents/webcontent/us_pro_sek-2_ug.pdf] If you want, copy and paste might work if this doesn't.
http://www.shure.com/idc/groups/tech_pubs/@global_managed/documents/webcontent/us_pro_sek-2_ug.pdf
http://www.shure.com/idc/groups/tech_pubs/@global_managed/documents/webcontent/us_pro_sek-2_ug.pdf