-sed -i 's/^DISABLED_MODULES=""/DISABLED_MODULES="fglrx nv"/' \
- /root/etc/default/linux-restricted-modules-common
+if [ -e /root/etc/default/linux-restricted-modules-common ]
+then
+ sed -i 's/^DISABLED_MODULES=""/DISABLED_MODULES="fglrx nv"/' \
+ /root/etc/default/linux-restricted-modules-common
+fi