I'm using the SWP 5.5 to sending a file to a scientific journal while they put in there website a LaTeX document class " http://th-www.if.uj.edu.pl/acta/latex/appolb.cls " and an empty paper which can be used as a template " http://th-www.if.uj.edu.pl/acta/latex/template.tex " the problème is when I launch this files with my SWP it could not be compiled and it give this errors : " characters in the file name or directory are invalid on some Tex systems " & "LaTex error : File 'appolb.cls' not found... enter new name or quit "

Please help me I really need to send this file.
Thanks in advance !