Googling this filename indicates a possible trojan... https://www.google.com/search?q=install_flashplayer11x32_aih.exe&ie=ut f-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a
However going directly to the adobe site from XP x64 machine with Firefox 20.0.1 is taking me here http://get.adobe.com/flashplayer/download/?installer=Flash_Player_11_f or_Other_Browsers&os=2003&browser_type=Gecko&browser_dist=Firefox and prompting me to download the filename that is potentially malicious.
Sooooo?