problems aiff to AC3 help

I have gone through the steps but for somee reason, i keep getting a message says " he file moms bday aiff cannot be used because an os error of type -50 occured0 is my problem one - my qt mpeg 2 movie is 48khz or two - my first mpeg move i made says studio pro.m2v is this a normal response since I am working in fcp making a qt mpeg2 movie all I am saying is I am trying to get pass the step of dropping my aiff file into the L side in A pack and it gives me an error do I need to make a Qt move al over again?

help
Jewels

are you exporting for DVD with compressor?

cos

Hello I have fcp 3 I do not have compresser with my fcp - i was told by Ken to use A-pack and all is good with A-pack ( I have simple directions and am following them just fine) until i have to drag my aiff or aif file into A-pack and gives me this message " the file May 13th Wendesday 09 aif cannot be used becasue an os error of type -50 ocurred" please help!

Jewels

Time to upgrade your FC Studio Jewels. It will make things much easier for you in both the near and long run. FC 3 is ancient by today's standards.
Steve