diff --git a/.travis.yml b/.travis.yml
index 429f10f..16da8a2 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -28,7 +28,7 @@ jobs:
       name: "Shellcheck lint"
       dist: linux
       script:
-        - shellcheck autoinstall/install.sh
+        - shellcheck auto_install/install.sh
         - find scripts/ -type f -exec shellcheck {} \;
 
     - stage: test
diff --git a/README.md b/README.md
index 98d4af0..4742a5a 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,7 @@
 ![WireGuard + OpenVPN logo](logos.jpg)
 
 **[Is pivpn.io down?](https://status.pivpn.io)** |
+[![Codacy Badge](https://api.codacy.com/project/badge/Grade/452112df3c2c435d93aacc113f546eae)](https://app.codacy.com/gh/pivpn/pivpn?utm_source=github.com&utm_medium=referral&utm_content=pivpn/pivpn&utm_campaign=Badge_Grade_Settings)
 **Test:** [![Build Status](https://travis-ci.com/pivpn/pivpn.svg?branch=test)](https://travis-ci.com/pivpn/pivpn) |
 **Master:** [![Build Status](https://travis-ci.com/pivpn/pivpn.svg?branch=master)](https://travis-ci.com/pivpn/pivpn)
 
diff --git a/auto_install/install.sh b/auto_install/install.sh
index 34850a6..6ba1625 100755
--- a/auto_install/install.sh
+++ b/auto_install/install.sh
@@ -28,7 +28,6 @@ debianOvpnUserGroup="openvpn:openvpn"
 
 ######## PKG Vars ########
 PKG_MANAGER="apt-get"
-PKG_CACHE="/var/lib/apt/lists/"
 ### FIXME: quoting UPDATE_PKG_CACHE and PKG_INSTALL hangs the script, shellcheck SC2086
 UPDATE_PKG_CACHE="${PKG_MANAGER} update -y"
 PKG_INSTALL="${PKG_MANAGER} --yes --no-install-recommends install"
@@ -438,8 +437,10 @@ preconfigurePackages(){
 		BASE_DEPS+=(dhcpcd5)
 	fi
 
-	AVAILABLE_OPENVPN="$(apt-cache policy openvpn | grep -m1 'Candidate: ' | grep -v '(none)' | awk '{print $2}')"
 	DPKG_ARCH="$(dpkg --print-architecture)"
+
+	AVAILABLE_OPENVPN="$(apt-cache policy openvpn | grep -m1 'Candidate: ' | grep -v '(none)' | awk '{print $2}')"
+	OPENVPN_SUPPORT=0
 	NEED_OPENVPN_REPO=0
 
 	# We require OpenVPN 2.4 or later for ECC support. If not available in the
@@ -461,6 +462,7 @@ preconfigurePackages(){
 	fi
 
 	AVAILABLE_WIREGUARD="$(apt-cache policy wireguard | grep -m1 'Candidate: ' | grep -v '(none)' | awk '{print $2}')"
+	WIREGUARD_SUPPORT=0
 
 	# If a wireguard kernel object is found and is part of any installed package, then
 	# it has not been build via DKMS or manually (installing via wireguard-dkms does not
@@ -534,14 +536,20 @@ installDependentPackages(){
 		fi
 	done
 
-	local APTLOGFILE="$($SUDO mktemp)"
+	local APTLOGFILE
+	APTLOGFILE="$($SUDO mktemp)"
 
-	if command -v debconf-apt-progress > /dev/null; then
-        # shellcheck disable=SC2086
-		$SUDO debconf-apt-progress --logfile "${APTLOGFILE}" -- ${PKG_INSTALL} "${TO_INSTALL[@]}"
-	else
+	if [ "${runUnattended}" = 'true' ]; then
 		# shellcheck disable=SC2086
 		$SUDO ${PKG_INSTALL} "${TO_INSTALL[@]}"
+	else
+		if command -v debconf-apt-progress > /dev/null; then
+			# shellcheck disable=SC2086
+			$SUDO debconf-apt-progress --logfile "${APTLOGFILE}" -- ${PKG_INSTALL} "${TO_INSTALL[@]}"
+		else
+			# shellcheck disable=SC2086
+			$SUDO ${PKG_INSTALL} "${TO_INSTALL[@]}"
+		fi
 	fi
 
 	local FAILED=0
@@ -684,7 +692,8 @@ validIP(){
 }
 
 validIPAndNetmask(){
-	local ip=$1
+	local ip
+	ip=$1
 	local stat=1
 	ip="${ip/\//.}"
 
@@ -763,9 +772,11 @@ getStaticIPv4Settings() {
 			echo "::: Skipping setting static IP address"
 		fi
 
-		echo "dhcpReserv=${dhcpReserv}" >> ${tempsetupVarsFile}
-		echo "IPv4addr=${IPv4addr}" >> ${tempsetupVarsFile}
-		echo "IPv4gw=${IPv4gw}" >> ${tempsetupVarsFile}
+		{
+		echo "dhcpReserv=${dhcpReserv}"
+		echo "IPv4addr=${IPv4addr}"
+		echo "IPv4gw=${IPv4gw}"
+		} >> ${tempsetupVarsFile}
 		return
 	fi
 
@@ -1099,6 +1110,13 @@ installPiVPN(){
 			# the user after the installation.
 			ALLOWED_IPS="0.0.0.0/0, ::0/0"
 		fi
+		# The default MTU should be fine for most users but we allow to set a
+		# custom MTU via unattend setupVARs file. Use default if not provided.
+		if [ -z "$pivpnMTU" ]; then
+			# Using default Wireguard MTU
+			pivpnMTU="1420"
+		fi
+    
 		CUSTOMIZE=0
 
 		installWireGuard
@@ -1109,13 +1127,16 @@ installPiVPN(){
 		confNetwork
 
 		echo "pivpnPROTO=${pivpnPROTO}" >> ${tempsetupVarsFile}
+		echo "pivpnMTU=${pivpnMTU}" >> ${tempsetupVarsFile}
 
 	fi
 
-	echo "pivpnDEV=${pivpnDEV}" >> ${tempsetupVarsFile}
-	echo "pivpnNET=${pivpnNET}" >> ${tempsetupVarsFile}
-	echo "subnetClass=${subnetClass}" >> ${tempsetupVarsFile}
-	echo "ALLOWED_IPS=\"${ALLOWED_IPS}\"" >> ${tempsetupVarsFile}
+	{
+	echo "pivpnDEV=${pivpnDEV}"
+	echo "pivpnNET=${pivpnNET}"
+	echo "subnetClass=${subnetClass}"
+	echo "ALLOWED_IPS=\"${ALLOWED_IPS}\""
+	} >> ${tempsetupVarsFile}
 }
 
 askWhichVPN(){
@@ -1243,11 +1264,15 @@ installWireGuard(){
 				exit 1
 			else
 				if (whiptail --title "Install WireGuard" --yesno "Your Raspberry Pi is running kernel package ${INSTALLED_KERNEL}, however the latest version is ${CANDIDATE_KERNEL}.\n\nInstalling WireGuard requires the latest kernel, so to continue, first you need to upgrade all packages, then reboot, and then run the script again.\n\nProceed to the upgrade?" ${r} ${c}); then
-					if command -v debconf-apt-progress &> /dev/null; then
-						# shellcheck disable=SC2086
-						$SUDO debconf-apt-progress -- ${PKG_MANAGER} upgrade -y
-					else
+					if [ "${runUnattended}" = 'true' ]; then
 						$SUDO ${PKG_MANAGER} upgrade -y
+					else
+						if command -v debconf-apt-progress &> /dev/null; then
+							# shellcheck disable=SC2086
+							$SUDO debconf-apt-progress -- ${PKG_MANAGER} upgrade -y
+						else
+							$SUDO ${PKG_MANAGER} upgrade -y
+						fi
 					fi
 					if (whiptail --title "Reboot" --yesno "You need to reboot after upgrading to run the new kernel.\n\nWould you like to reboot now?" ${r} ${c}); then
 						whiptail --title "Rebooting" --msgbox "The system will now reboot.\n\nWhen you come back, just run the installation command again:\n\n    curl -L https://install.pivpn.io | bash" ${r} ${c}
@@ -1267,7 +1292,7 @@ installWireGuard(){
 		echo "::: Installing WireGuard from Debian package... "
 
 		if [ -z "$AVAILABLE_WIREGUARD" ]; then
-			echo "::: Adding Raspbian repository... "
+			echo "::: Adding Raspbian Bullseye repository... "
 			echo "deb http://raspbian.raspberrypi.org/raspbian/ bullseye main" | $SUDO tee /etc/apt/sources.list.d/pivpn-bullseye-repo.list > /dev/null
 
 			# Do not upgrade packages from the bullseye repository except for wireguard
@@ -1279,7 +1304,13 @@ installWireGuard(){
 		fi
 
 		# qrencode is used to generate qrcodes from config file, for use with mobile clients
-		PIVPN_DEPS=(raspberrypi-kernel-headers wireguard-tools wireguard-dkms qrencode)
+		PIVPN_DEPS=(wireguard-tools qrencode)
+
+		if [ "$WIREGUARD_BUILTIN" -eq 0 ]; then
+			# Explicitly install the module if not built-in
+			PIVPN_DEPS+=(raspberrypi-kernel-headers wireguard-dkms)
+		fi
+
 		installDependentPackages PIVPN_DEPS[@]
 
 	elif [ "$PLAT" = "Debian" ]; then
@@ -1287,7 +1318,7 @@ installWireGuard(){
 		echo "::: Installing WireGuard from Debian package... "
 
 		if [ -z "$AVAILABLE_WIREGUARD" ]; then
-			echo "::: Adding Debian repository... "
+			echo "::: Adding Debian Bullseye repository... "
 			echo "deb https://deb.debian.org/debian/ bullseye main" | $SUDO tee /etc/apt/sources.list.d/pivpn-bullseye-repo.list > /dev/null
 
 			printf 'Package: *\nPin: release n=bullseye\nPin-Priority: -1\n\nPackage: wireguard wireguard-dkms wireguard-tools\nPin: release n=bullseye\nPin-Priority: 100\n' | $SUDO tee /etc/apt/preferences.d/pivpn-limit-bullseye > /dev/null
@@ -1750,9 +1781,11 @@ askEncryption(){
 			fi
 		fi
 
-		echo "TWO_POINT_FOUR=${TWO_POINT_FOUR}" >> ${tempsetupVarsFile}
-		echo "pivpnENCRYPT=${pivpnENCRYPT}" >> ${tempsetupVarsFile}
-		echo "USE_PREDEFINED_DH_PARAM=${USE_PREDEFINED_DH_PARAM}" >> ${tempsetupVarsFile}
+		{
+		echo "TWO_POINT_FOUR=${TWO_POINT_FOUR}"
+		echo "pivpnENCRYPT=${pivpnENCRYPT}"
+		echo "USE_PREDEFINED_DH_PARAM=${USE_PREDEFINED_DH_PARAM}"
+		} >> ${tempsetupVarsFile}
 		return
 	fi
 
@@ -1760,9 +1793,11 @@ askEncryption(){
 		if [ "$VPN" = "openvpn" ]; then
 			TWO_POINT_FOUR=1
 			pivpnENCRYPT=256
-			echo "TWO_POINT_FOUR=${TWO_POINT_FOUR}" >> ${tempsetupVarsFile}
-			echo "pivpnENCRYPT=${pivpnENCRYPT}" >> ${tempsetupVarsFile}
-			echo "USE_PREDEFINED_DH_PARAM=${USE_PREDEFINED_DH_PARAM}" >> ${tempsetupVarsFile}
+			{
+			echo "TWO_POINT_FOUR=${TWO_POINT_FOUR}"
+			echo "pivpnENCRYPT=${pivpnENCRYPT}"
+			echo "USE_PREDEFINED_DH_PARAM=${USE_PREDEFINED_DH_PARAM}"
+			} >> ${tempsetupVarsFile}
 			return
 		fi
 	fi
@@ -1795,15 +1830,17 @@ askEncryption(){
 		USE_PREDEFINED_DH_PARAM=0
 	fi
 
-	echo "TWO_POINT_FOUR=${TWO_POINT_FOUR}" >> ${tempsetupVarsFile}
-	echo "pivpnENCRYPT=${pivpnENCRYPT}" >> ${tempsetupVarsFile}
-	echo "USE_PREDEFINED_DH_PARAM=${USE_PREDEFINED_DH_PARAM}" >> ${tempsetupVarsFile}
+	{
+	echo "TWO_POINT_FOUR=${TWO_POINT_FOUR}"
+	echo "pivpnENCRYPT=${pivpnENCRYPT}"
+	echo "USE_PREDEFINED_DH_PARAM=${USE_PREDEFINED_DH_PARAM}"
+	} >> ${tempsetupVarsFile}
 }
 
 cidrToMask(){
 	# Source: https://stackoverflow.com/a/20767392
 	set -- $(( 5 - ($1 / 8) )) 255 255 255 255 $(( (255 << (8 - ($1 % 8))) & 255 )) 0 0 0
-	[ $1 -gt 1 ] && shift $1 || shift
+	shift $1
 	echo ${1-0}.${2-0}.${3-0}.${4-0}
 }
 
@@ -2060,6 +2097,7 @@ confWireGuard(){
 	echo "[Interface]
 PrivateKey = $($SUDO cat /etc/wireguard/keys/server_priv)
 Address = ${vpnGw}/${subnetClass}
+MTU = ${pivpnMTU}
 ListenPort = ${pivpnPORT}" | $SUDO tee /etc/wireguard/wg0.conf &> /dev/null
 	echo "::: Server config generated."
 }
@@ -2091,7 +2129,7 @@ confNetwork(){
 			$SUDO sed "/delete these required/i *nat\n:POSTROUTING ACCEPT [0:0]\n-I POSTROUTING -s ${pivpnNET}\/${subnetClass} -o ${IPv4dev} -j MASQUERADE -m comment --comment ${VPN}-nat-rule\nCOMMIT\n" -i /etc/ufw/before.rules
 		fi
 		# Insert rules at the beginning of the chain (in case there are other rules that may drop the traffic)
-		$SUDO ufw insert 1 allow "${pivpnPORT}"/"${pivpnPROTO}" >/dev/null
+		$SUDO ufw insert 1 allow "${pivpnPORT}"/"${pivpnPROTO}" comment allow-${VPN} >/dev/null
 		$SUDO ufw route insert 1 allow in on "${pivpnDEV}" from "${pivpnNET}/${subnetClass}" out on "${IPv4dev}" to any >/dev/null
 
 		$SUDO ufw reload >/dev/null
diff --git a/examples/unattended_wireguard_example.conf b/examples/unattended_wireguard_example.conf
index 2fb67a8..c8e354e 100644
--- a/examples/unattended_wireguard_example.conf
+++ b/examples/unattended_wireguard_example.conf
@@ -4,6 +4,7 @@ VPN=wireguard
 pivpnNET=10.6.0.0
 subnetClass=24
 ALLOWED_IPS="0.0.0.0/0, ::0/0"
+pivpnMTU=1420
 pivpnPORT=51820
 pivpnDNS1=9.9.9.9
 pivpnDNS2=149.112.112.112
diff --git a/scripts/openvpn/bash-completion b/scripts/openvpn/bash-completion
index 1b9ef7e..db7540e 100644
--- a/scripts/openvpn/bash-completion
+++ b/scripts/openvpn/bash-completion
@@ -1,3 +1,4 @@
+#!/bin/bash
 _pivpn()
 {
     local cur prev opts
diff --git a/scripts/openvpn/makeOVPN.sh b/scripts/openvpn/makeOVPN.sh
index b03af64..5734f66 100755
--- a/scripts/openvpn/makeOVPN.sh
+++ b/scripts/openvpn/makeOVPN.sh
@@ -25,7 +25,7 @@ helpFunc() {
     echo "::: Commands:"
     echo ":::  [none]               Interactive mode"
     echo ":::  nopass               Create a client without a password"
-    echo ":::  -n,--name            Name for the Client (default: '"$(hostname)"')"
+    echo ":::  -n,--name            Name for the Client (default: \"$(hostname)\")"
     echo ":::  -p,--password        Password for the Client (no default)"
     echo ":::  -d,--days            Expire the certificate after specified number of days (default: 1080)"
     echo ":::  -b,--bitwarden       Create and save a client through Bitwarden"
@@ -133,7 +133,7 @@ function useBitwarden() {
     # login and unlock vault
     printf "****Bitwarden Login****"
     printf "\n"
-    SESSION_KEY=`bw login --raw`
+    SESSION_KEY=$(bw login --raw)
     export BW_SESSION=$SESSION_KEY
     printf "Successfully Logged in!"
     printf "\n"
@@ -168,7 +168,7 @@ function useBitwarden() {
     printf "Creating a PiVPN item for your vault..."
     printf "\n"
     # create a new item for your PiVPN Password
-    PASSWD=`bw generate -usln --length $LENGTH`
+    PASSWD=$(bw generate -usln --length $LENGTH)
     bw get template item | jq '.login.type = "1"'| jq '.name = "PiVPN"' | jq -r --arg NAME "$NAME" '.login.username = $NAME' | jq -r --arg PASSWD "$PASSWD" '.login.password = $PASSWD' |  bw encode | bw create item
     bw logout
 
@@ -422,7 +422,7 @@ fi
 cidrToMask(){
 	# Source: https://stackoverflow.com/a/20767392
 	set -- $(( 5 - ($1 / 8) )) 255 255 255 255 $(( (255 << (8 - ($1 % 8))) & 255 )) 0 0 0
-	[ $1 -gt 1 ] && shift $1 || shift
+	shift $1
 	echo ${1-0}.${2-0}.${3-0}.${4-0}
 }
 
diff --git a/scripts/openvpn/removeOVPN.sh b/scripts/openvpn/removeOVPN.sh
index a77333b..ef58cb1 100755
--- a/scripts/openvpn/removeOVPN.sh
+++ b/scripts/openvpn/removeOVPN.sh
@@ -60,7 +60,7 @@ if [[ -z "${CERTS_TO_REVOKE}" ]]; then
                 # Prevent printing "server" certificate
                 CERTS[$i]=$(echo -e "${NAME}")
             fi
-            let i=i+1
+            ((i++))
         fi
     done <${INDEX}
     
@@ -82,7 +82,7 @@ if [[ -z "${CERTS_TO_REVOKE}" ]]; then
 
     re='^[0-9]+$'
     if [[ ${NAME} =~ $re ]] ; then
-        NAME=${CERTS[$(($NAME))]}
+        NAME=${CERTS[$((NAME))]}
     fi
 
     for((x=1;x<=i;++x)); do
@@ -104,7 +104,7 @@ else
         if [[ "${STATUS}" = "V" ]]; then
             NAME=$(echo -e "$line" | sed -e 's:.*/CN=::')
             CERTS[$i]=${NAME}
-            let i=i+1
+            ((i++))
         fi
     done <${INDEX}
 
diff --git a/scripts/wireguard/bash-completion b/scripts/wireguard/bash-completion
index ae57b41..2c18f9d 100644
--- a/scripts/wireguard/bash-completion
+++ b/scripts/wireguard/bash-completion
@@ -1,9 +1,9 @@
+#!/bin/bash
 _pivpn()
 {
-    local cur prev opts
+    local cur opts
     COMPREPLY=()
     cur="${COMP_WORDS[COMP_CWORD]}"
-    prev="${COMP_WORDS[COMP_CWORD-1]}"
     dashopts="-a -c -d -l -qr -r -h -u -up -bk -off -on"
     opts="add clients debug list qrcode remove help uninstall update backup (temp) off (temp) on"
     if [ "${#COMP_WORDS[@]}" -eq 2 ]
diff --git a/scripts/wireguard/clientSTAT.sh b/scripts/wireguard/clientSTAT.sh
index f47e800..139b09d 100755
--- a/scripts/wireguard/clientSTAT.sh
+++ b/scripts/wireguard/clientSTAT.sh
@@ -2,7 +2,6 @@
 # PiVPN: client status script
 
 CLIENTS_FILE="/etc/wireguard/configs/clients.txt"
-CONF_FILE="/etc/wireguard/wg0.conf"
 
 if [ ! -s "$CLIENTS_FILE" ]; then
     echo "::: There are no clients to list"
diff --git a/scripts/wireguard/disableCONF.sh b/scripts/wireguard/disableCONF.sh
index 7d3d682..7595110 100755
--- a/scripts/wireguard/disableCONF.sh
+++ b/scripts/wireguard/disableCONF.sh
@@ -44,7 +44,7 @@ do
     shift
 done
 
-cd /etc/wireguard
+cd /etc/wireguard || exit
 if [ ! -s configs/clients.txt ]; then
     echo "::: There are no clients to change"
     exit 1
@@ -81,7 +81,7 @@ for CLIENT_NAME in "${CLIENTS_TO_CHANGE[@]}"; do
 
     re='^[0-9]+$'
     if [[ ${CLIENT_NAME} =~ $re ]] ; then
-        CLIENT_NAME=${LIST[$(($CLIENT_NAME -1))]}
+        CLIENT_NAME=${LIST[$((CLIENT_NAME -1))]}
     fi
 
     if ! grep -q "^${CLIENT_NAME} " configs/clients.txt; then
diff --git a/scripts/wireguard/enableCONF.sh b/scripts/wireguard/enableCONF.sh
index 4ce0cf7..82331fd 100755
--- a/scripts/wireguard/enableCONF.sh
+++ b/scripts/wireguard/enableCONF.sh
@@ -44,7 +44,7 @@ do
     shift
 done
 
-cd /etc/wireguard
+cd /etc/wireguard || exit
 if [ ! -s configs/clients.txt ]; then
     echo "::: There are no clients to change"
     exit 1
@@ -79,7 +79,7 @@ for CLIENT_NAME in "${CLIENTS_TO_CHANGE[@]}"; do
 
     re='^[0-9]+$'
     if [[ ${CLIENT_NAME} =~ $re ]] ; then
-        CLIENT_NAME=${LIST[$(($CLIENT_NAME -1))]}
+        CLIENT_NAME=${LIST[$((CLIENT_NAME -1))]}
     fi
 
     if ! grep -q "^${CLIENT_NAME} " configs/clients.txt; then
diff --git a/scripts/wireguard/listCONF.sh b/scripts/wireguard/listCONF.sh
index 150eb5a..c89bae3 100755
--- a/scripts/wireguard/listCONF.sh
+++ b/scripts/wireguard/listCONF.sh
@@ -1,6 +1,6 @@
 #!/bin/bash
 
-cd /etc/wireguard/configs
+cd /etc/wireguard/configs || exit
 if [ ! -s clients.txt ]; then
     echo "::: There are no clients to list"
     exit 1
diff --git a/scripts/wireguard/makeCONF.sh b/scripts/wireguard/makeCONF.sh
index 73bfd9b..abff296 100755
--- a/scripts/wireguard/makeCONF.sh
+++ b/scripts/wireguard/makeCONF.sh
@@ -53,7 +53,7 @@ if [ ! -d "${install_home}/configs" ]; then
     chmod 0750 "${install_home}/configs"
 fi
 
-cd /etc/wireguard
+cd /etc/wireguard || exit
 
 if [ -z "${CLIENT_NAME}" ]; then
     read -r -p "Enter a Name for the Client: " CLIENT_NAME
@@ -94,11 +94,15 @@ done
 
 NET_REDUCED="${pivpnNET::-2}"
 
-echo -n "[Interface]
+echo "[Interface]
 PrivateKey = $(cat "keys/${CLIENT_NAME}_priv")
-Address = ${NET_REDUCED}.${COUNT}/${subnetClass}
-DNS = ${pivpnDNS1}" > "configs/${CLIENT_NAME}.conf"
+Address = ${NET_REDUCED}.${COUNT}/${subnetClass}" > "configs/${CLIENT_NAME}.conf"
 
+if [ -n "${pivpnMTU}" ]; then
+    echo "MTU = ${pivpnMTU}" >> "configs/${CLIENT_NAME}.conf"
+fi
+
+echo -n "DNS = ${pivpnDNS1}" >> "configs/${CLIENT_NAME}.conf"
 if [ -n "${pivpnDNS2}" ]; then
     echo ", ${pivpnDNS2}" >> "configs/${CLIENT_NAME}.conf"
 else
diff --git a/scripts/wireguard/pivpnDEBUG.sh b/scripts/wireguard/pivpnDEBUG.sh
index 5f59f3e..6d8dd64 100755
--- a/scripts/wireguard/pivpnDEBUG.sh
+++ b/scripts/wireguard/pivpnDEBUG.sh
@@ -19,7 +19,7 @@ echo -e "::::\t    \e[4mInstallation settings\e[0m    \t ::::"
 sed "s/$pivpnHOST/REDACTED/" < ${setupVars}
 printf "=============================================\n"
 echo -e "::::  \e[4mServer configuration shown below\e[0m   ::::"
-cd /etc/wireguard/keys
+cd /etc/wireguard/keys || exit
 cp ../wg0.conf ../wg0.tmp
 # Replace every key in the server configuration with just its file name
 for k in *; do
diff --git a/scripts/wireguard/qrcodeCONF.sh b/scripts/wireguard/qrcodeCONF.sh
index 6d980fe..c114752 100755
--- a/scripts/wireguard/qrcodeCONF.sh
+++ b/scripts/wireguard/qrcodeCONF.sh
@@ -27,7 +27,7 @@ do
     shift
 done
 
-cd /etc/wireguard/configs
+cd /etc/wireguard/configs || exit
 if [ ! -s clients.txt ]; then
     echo "::: There are no clients to show"
     exit 1
@@ -55,7 +55,7 @@ fi
 for CLIENT_NAME in "${CLIENTS_TO_SHOW[@]}"; do
     re='^[0-9]+$'
     if [[ ${CLIENT_NAME} =~ $re ]] ; then
-        CLIENT_NAME=${LIST[$(($CLIENT_NAME -1))]}
+        CLIENT_NAME=${LIST[$((CLIENT_NAME -1))]}
     fi    
     if grep -qw "${CLIENT_NAME}" clients.txt; then
         echo -e "::: Showing client \e[1m${CLIENT_NAME}\e[0m below"
diff --git a/scripts/wireguard/removeCONF.sh b/scripts/wireguard/removeCONF.sh
index 95c6ffa..0de7671 100755
--- a/scripts/wireguard/removeCONF.sh
+++ b/scripts/wireguard/removeCONF.sh
@@ -40,7 +40,7 @@ do
     shift
 done
 
-cd /etc/wireguard
+cd /etc/wireguard || exit
 if [ ! -s configs/clients.txt ]; then
     echo "::: There are no clients to remove"
     exit 1
@@ -70,7 +70,7 @@ for CLIENT_NAME in "${CLIENTS_TO_REMOVE[@]}"; do
 
     re='^[0-9]+$'
     if [[ ${CLIENT_NAME} =~ $re ]] ; then
-        CLIENT_NAME=${LIST[$(($CLIENT_NAME -1))]}
+        CLIENT_NAME=${LIST[$((CLIENT_NAME -1))]}
     fi
 
     if ! grep -q "^${CLIENT_NAME} " configs/clients.txt; then