After Effects can't import files

[xiaoxu5101]

I installed After Effects 6 to my Mac G4, but when I try to import file into it, I got a message said "unicode failed", and "internal structure damage". Then the whole program quit.
My questions are those problem is from the software it self or from my computer? Is possible to fix? How?
Thanks.

 

[iris_failsafe]

It is a problem of your OS. It looks like a file is missing. Or the installation AF disc in incomplete. Use the original disc to do the installation, if you are using it, you probably have to reinstall Mac OS X

 

[xiaoxu5101]

How can I reinstall the OS X?