I am using CXA 9000A SA with EMC option installed. I want to use the available mask files for 802.11p 5MHz and 10MHz system. I see them copied on a directory on my instrument, but I can't select them (even see them) using the method *Recall, Data (Import), Open*., because the extension *.mask is unavailable. My instrument doesn't have N9077A & W9077A installed. Please comment.