Mavericks - Tell application "Preview" open PDF - strange permission issue
for me do shell script.. failed, but this one below worked.

set filepath to POSIX path of "Users:student:Desktop:Yourfile.pdf"
try
    set command to "open " &amp; quoted form of filepath
    do shell script command
end try

Note: Instead of ":" for file path I used "/", a modification one can try.

Source of Code: MacRumors