diff --git a/puffin_http/src/client.rs b/puffin_http/src/client.rs
index 2b7bb429..d24e9aa1 100644
--- a/puffin_http/src/client.rs
+++ b/puffin_http/src/client.rs
@@ -116,7 +116,7 @@ pub fn consume_message(stream: &mut impl std::io::Read) -> anyhow::Result<puffin
         std::cmp::Ordering::Equal => {}
         std::cmp::Ordering::Greater => {
             anyhow::bail!(
-                "puffin server is using a newer protocol version ({}) than the client ({}). Update puffin_viewer with 'cargo install puffin_viewer'.",
+                "puffin server is using a newer protocol version ({}) than the client ({}). Update puffin_viewer with 'cargo install puffin_viewer --locked'.",
                 server_version,
                 crate::PROTOCOL_VERSION
             );
diff --git a/puffin_viewer/README.md b/puffin_viewer/README.md
index 4b82f7e7..c1f63052 100644
--- a/puffin_viewer/README.md
+++ b/puffin_viewer/README.md
@@ -7,7 +7,7 @@
 Use [`puffin_http`](https://github.com/EmbarkStudios/puffin/tree/main/puffin_http) to publish puffin events over TCP. Then connect to it with `puffin_viewer`:
 
 ``` sh
-cargo install puffin_viewer
+cargo install puffin_viewer --locked
 puffin_viewer --url 127.0.0.1:8585
 ```
 
diff --git a/puffin_viewer/src/lib.rs b/puffin_viewer/src/lib.rs
index 3b7383b7..f2f44a9f 100644
--- a/puffin_viewer/src/lib.rs
+++ b/puffin_viewer/src/lib.rs
@@ -232,7 +232,7 @@ impl eframe::App for PuffinViewer {
                 ui.heading("Puffin Viewer, on the web");
                 ui.horizontal_wrapped(|ui| {
                     ui.label("It is recommended that you instead use the native version: ");
-                    ui.code("cargo install puffin_viewer");
+                    ui.code("cargo install puffin_viewer --locked");
                 });
                 ui.hyperlink("https://github.com/EmbarkStudios/puffin");
             });