diff --git a/Cargo.toml b/Cargo.toml
index 0d56d71..7c76d0e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 name = "vopono"
 description = "Launch applications via VPN tunnels using temporary network namespaces"
-version = "0.10.7"
+version = "0.10.8"
 authors = ["James McMurray <jamesmcm03@gmail.com>"]
 edition = "2021"
 license = "GPL-3.0-or-later"
diff --git a/README.md b/README.md
index 2e7b0df..71049c5 100644
--- a/README.md
+++ b/README.md
@@ -43,7 +43,7 @@ lynx all running through different VPN connections:
 
 \*\*\* For ProtonVPN you can generate and download specific Wireguard config
 files, and use them as a custom provider config. See the [User Guide](USERGUIDE.md)
-for details. [Port Forwarding](https://protonvpn.com/support/port-forwarding-manual-setup/) is supported with the `--protonvpn-port-forwarding` argument for both OpenVPN and Wireguard (with `--provider custom --custom xxx.conf --protocol wireguard` ), note for OpenVPN you must generate the OpenVPN config files appending `+pmp` to your OpenVPN username, and you must choose servers which support this feature (e.g. at the time of writing, the Romania servers do). The assigned port is then printed to the terminal where vopono was launched - this should then be set in any applications that require it.
+for details. [Port Forwarding](https://protonvpn.com/support/port-forwarding-manual-setup/) is supported with the `--protonvpn-port-forwarding` argument for both OpenVPN and Wireguard (with `--provider custom --custom xxx.conf --protocol wireguard` ). `natpmpc` must be installed. Note for OpenVPN you must generate the OpenVPN config files appending `+pmp` to your OpenVPN username, and you must choose servers which support this feature (e.g. at the time of writing, the Romania servers do). The assigned port is then printed to the terminal where vopono was launched - this should then be set in any applications that require it.
 
 
 \*\*\*\* Cloudflare Warp uses its own protocol. Set both the provider and
diff --git a/USERGUIDE.md b/USERGUIDE.md
index 3580530..418309f 100644
--- a/USERGUIDE.md
+++ b/USERGUIDE.md
@@ -479,6 +479,8 @@ $ vopono -v exec --provider custom --custom testwg-UK-17.conf --protocol wiregua
 
 Port forwarding can be enabled with the `--protonvpn-port-forwarding` argument, but requires using a server that supports port forwarding. 
 
+`natpmpc` must be installed e.g. via the `libnatpmp` package on Arch Linux.
+
 Note for OpenVPN you must generate the OpenVPN config files appending `+pmp` to your OpenVPN username (i.e. what will be written to `~/.config/vopono/proton/openvpn/auth.txt`)
 
 Note the usual `-o` / `--open-ports` argument has no effect here as we only know the port number assigned after connecting to ProtonVPN.
diff --git a/vopono_core/Cargo.toml b/vopono_core/Cargo.toml
index fb6a1d4..f98e707 100644
--- a/vopono_core/Cargo.toml
+++ b/vopono_core/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 name = "vopono_core"
 description = "Library code for running VPN connections in network namespaces"
-version = "0.1.7"
+version = "0.1.8"
 edition = "2021"
 authors = ["James McMurray <jamesmcm03@gmail.com>"]
 license = "GPL-3.0-or-later"
diff --git a/vopono_core/src/network/natpmpc.rs b/vopono_core/src/network/natpmpc.rs
index 4910b3e..93a1894 100644
--- a/vopono_core/src/network/natpmpc.rs
+++ b/vopono_core/src/network/natpmpc.rs
@@ -23,6 +23,16 @@ impl Natpmpc {
     pub fn new(ns: &NetworkNamespace) -> anyhow::Result<Self> {
         let gateway_str = PROTONVPN_GATEWAY.to_string();
 
+        if let Err(x) = which::which("natpmpc") {
+            log::error!(
+                "natpmpc not found. Is natpmpc installed and on PATH? (e.g. libnatpmp package)"
+            );
+            return Err(anyhow::anyhow!(
+                "natpmpc not found. Is natpmpc installed and on PATH?: {:?}",
+                x
+            ));
+        }
+
         // Check output for readnatpmpresponseorretry returned 0 (OK)
         // If receive readnatpmpresponseorretry returned -7
         // Then prompt user to choose different gateway