A Debian server? That is not one of the supported platforms right? Did you use the platform override command when you initially installed it?
EDIT: Ah, I see you are running Debian 5. Looking at the download page, I see the following:
Not sure what deprecated means in relation to Debian 5 being a supported platform since they obviously have download links for it.
Debian 5 64bit x86 (MD5) DEPRECATED 32bit x86 (MD5) DEPRECATED
EDIT: Check to make sure you are root user and then examine the install log file.
EDIT: Give the full install a shot...but make sure you have a good, verified backup 1st.