diff --git a/lib.sh b/lib.sh
index 80c9c06..91af5b7 100755
--- a/lib.sh
+++ b/lib.sh
@@ -102,6 +102,8 @@ function get_package_name_ver {
 #   Sorted list of space delimited package name=version pairs.
 ###############################################################################
 function get_normalized_package_list {
+  # Update Apt cache
+  apt-get update
   # Remove commas, and block scalar folded backslashes,
   # extraneous spaces at the middle, beginning and end
   # then sort.