Quartus can't find shared library

Thanks for your prompt reply.

I think I have set up the variables as you suggested, but no joy.

<<

~:echo $QUARTUS_ROOTDIR_OVERIDE

/alt

~:echo $LD_LIBRARY_PATH

/lib

~:/alt/quartus/bin/quartus

quartus: error while loading shared libraries: libpng12.so.0: cannot open shared object file: No such file or directory

>>

<<

rut/lib\:ll *png*

lrwxrwxrwx 1 root root 18 Feb 24 08:45 libpng12.so.0 -> libpng12.so.0.44.0

-rwxrwxrwx 1 root root 155360 Feb 15 10:09 libpng12.so.0.44.0

>>

I guess I should have accepted the default location?

Thanks again for your help.

Marion