diff --git a/build/linux/usr/local/etc/omc/script/setup.sh b/build/linux/usr/local/etc/omc/script/setup.sh
index b5ff685f..51942e99 100644
--- a/build/linux/usr/local/etc/omc/script/setup.sh
+++ b/build/linux/usr/local/etc/omc/script/setup.sh
@@ -78,7 +78,7 @@ fi
 if [ -n "$M_PARAM" ]; then
   # Check that mode is within the standard range
   if [[ "$M_PARAM" != "standard" && "$M_PARAM" != "lite" ]]; then
-      echo "Error: -m can only be 'standard' or 'lite'."
+      echo "Error: M_PARAM can only be 'standard' or 'lite'."
       exit 1
   fi
   sed -i "s/MODE=.*/MODE=${M_PARAM}/" $VariableFile
@@ -91,7 +91,7 @@ fi
 if [ -n "$C_PARAM" ]; then
   # Check if customize is within the standard
   if [[ "$C_PARAM" != "omc" && "$C_PARAM" != "agt" && "$C_PARAM" != "ba" ]]; then
-      echo "Error: -c can only be 'omc', 'agt' or 'ba'."
+      echo "Error: C_PARAM can only be 'omc', 'agt' or 'ba'."
       exit 1
   fi
   sed -i "s/VENDORS=.*/VENDORS=${C_PARAM}/" $VariableFile
@@ -101,9 +101,7 @@ fi
 
 # =========================
 if [[ "$T_PARAM" == "install" && "$MODE" == "standard" ]]; then
-  if command -v mysql &> /dev/null || command -v mariadb &> /dev/null; then
-      echo "MySQL or MariaDB installed"
-  else
+  if ! command -v mysql &> /dev/null && ! command -v mariadb &> /dev/null; then
       echo "MySQL or MariaDB not installed"
       exit 1
   fi
diff --git a/build/pkg/deb/DEBIAN/postinst b/build/pkg/deb/DEBIAN/postinst
index 257f5592..e65cee55 100644
--- a/build/pkg/deb/DEBIAN/postinst
+++ b/build/pkg/deb/DEBIAN/postinst
@@ -27,7 +27,7 @@ if [ ! -f $RootDir/omc.conf ]; then
     fi
     if [ $? -ne 0 ]; then
       echo "Initialization failure."
-      dpkg --purge omc
+      rm -rf $RootDir
       exit 1
     fi