diff --git a/scripts/install b/scripts/install
index 31ba72f..c8627de 100644
--- a/scripts/install
+++ b/scripts/install
@@ -28,7 +28,7 @@ tmplog=$(mktemp /tmp/netdata-updater-log-XXXXXX.log)
 
 pushd "$NETDATA_TMPDIR"
     # the installer.sh script will append "netdata" after the --install-prefix arg
-    if !./netdata-installer.sh --install-prefix /var/www/ --dont-wait --disable-cloud --disable-telemetry --stable-channel > "$tmplog" 2>&1; then
+    if ! ./netdata-installer.sh --install-prefix /var/www/ --dont-wait --disable-cloud --disable-telemetry --stable-channel > "$tmplog" 2>&1; then
         tail -n50 $tmplog
         ynh_die "FAILED TO COMPILE/INSTALL NETDATA"
     fi
diff --git a/scripts/restore b/scripts/restore
index b1c96d2..c4a8e81 100644
--- a/scripts/restore
+++ b/scripts/restore
@@ -33,7 +33,7 @@ tmplog=$(mktemp /tmp/netdata-updater-log-XXXXXX.log)
 
 pushd "$NETDATA_TMPDIR"
     # the installer.sh script will append "netdata" after the --install-prefix arg
-    if !./netdata-installer.sh --install-prefix /var/www/ --dont-wait --disable-cloud --disable-telemetry --stable-channel > "$tmplog" 2>&1; then
+    if ! ./netdata-installer.sh --install-prefix /var/www/ --dont-wait --disable-cloud --disable-telemetry --stable-channel > "$tmplog" 2>&1; then
         tail -n50 $tmplog
         ynh_die "FAILED TO COMPILE/INSTALL NETDATA"
     fi
diff --git a/scripts/upgrade b/scripts/upgrade
index 89f8bab..43c6b59 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -38,7 +38,7 @@ tmplog=$(mktemp /tmp/netdata-updater-log-XXXXXX.log)
 
 pushd "$NETDATA_TMPDIR"
 	# the installer.sh script will append "netdata" after the --install-prefix arg
-	if !./netdata-installer.sh --install-prefix /var/www/ --dont-wait --disable-cloud --disable-telemetry --stable-channel > "$tmplog" 2>&1; then
+	if ! ./netdata-installer.sh --install-prefix /var/www/ --dont-wait --disable-cloud --disable-telemetry --stable-channel > "$tmplog" 2>&1; then
         tail -n50 $tmplog
         ynh_die "FAILED TO COMPILE/INSTALL NETDATA"
     fi