diff --git a/.github/workflows/ic-ref.yml b/.github/workflows/ic-ref.yml
index eb94f4ef..d865e1a6 100644
--- a/.github/workflows/ic-ref.yml
+++ b/.github/workflows/ic-ref.yml
@@ -29,7 +29,7 @@ jobs:
       - name: Install dfx
         uses: dfinity/setup-dfx@main
         with:
-          dfx-version: "0.24.2"
+          dfx-version: "0.24.3"
 
       - name: Cargo cache
         uses: actions/cache@v4
diff --git a/ic-agent/src/agent/response_authentication.rs b/ic-agent/src/agent/response_authentication.rs
index 3f252f6b..4a50a18b 100644
--- a/ic-agent/src/agent/response_authentication.rs
+++ b/ic-agent/src/agent/response_authentication.rs
@@ -108,11 +108,12 @@ pub(crate) fn lookup_rejection<Storage: AsRef<[u8]>>(
 ) -> Result<RequestStatusResponse, AgentError> {
     let reject_code = lookup_reject_code(certificate, request_id)?;
     let reject_message = lookup_reject_message(certificate, request_id)?;
+    let error_code = lookup_error_code(certificate, request_id)?;
 
     Ok(RequestStatusResponse::Rejected(RejectResponse {
         reject_code,
         reject_message,
-        error_code: None,
+        error_code,
     }))
 }
 
@@ -144,6 +145,23 @@ pub(crate) fn lookup_reject_message<Storage: AsRef<[u8]>>(
     Ok(from_utf8(msg)?.to_string())
 }
 
+pub(crate) fn lookup_error_code<Storage: AsRef<[u8]>>(
+    certificate: &Certificate<Storage>,
+    request_id: &RequestId,
+) -> Result<Option<String>, AgentError> {
+    let path = [
+        "request_status".as_bytes(),
+        request_id.as_slice(),
+        "error_code".as_bytes(),
+    ];
+    let msg = lookup_value(&certificate.tree, path);
+    match msg {
+        Ok(val) => Ok(Some(from_utf8(val)?.to_string())),
+        Err(AgentError::LookupPathAbsent(_)) => Ok(None),
+        Err(e) => Err(e),
+    }
+}
+
 pub(crate) fn lookup_reply<Storage: AsRef<[u8]>>(
     certificate: &Certificate<Storage>,
     request_id: &RequestId,
diff --git a/ref-tests/tests/ic-ref.rs b/ref-tests/tests/ic-ref.rs
index b0ab8b5e..edb371cf 100644
--- a/ref-tests/tests/ic-ref.rs
+++ b/ref-tests/tests/ic-ref.rs
@@ -515,8 +515,9 @@ mod management_canister {
                     Err(AgentError::CertifiedReject(RejectResponse {
                         reject_code: RejectCode::CanisterError,
                         reject_message,
-                        error_code: None,
+                        error_code: Some(error_code),
                     })) if reject_message.contains(&format!("Canister {canister_id}: Canister has no update method 'update'"))
+                        && error_code == "IC0536"
                 ),
                 "wrong error: {result:?}"
             );
@@ -739,7 +740,7 @@ mod management_canister {
 
             let args = Argument::from_candid((create_args,));
 
-            let creation_fee = 100_000_000_000;
+            let creation_fee = 500_000_000_000;
             let canister_initial_balance = 4_000_000_000;
             let (create_result,): (CreateResult,) = wallet
                 .call(
@@ -1247,8 +1248,8 @@ mod extras {
                     Err(AgentError::CertifiedReject(RejectResponse {
                         reject_code: RejectCode::CanisterError,
                         reject_message,
-                        error_code: None,
-                    })) if reject_message.contains("Canister iimsn-6yaaa-aaaaa-afiaa-cai is already installed")
+                        error_code: Some(code),
+                    })) if reject_message.contains("Canister iimsn-6yaaa-aaaaa-afiaa-cai is already installed") && code == "IC0538"
                 ),
                 "wrong error: {result:?}"
             );
diff --git a/ref-tests/tests/integration.rs b/ref-tests/tests/integration.rs
index b026c206..17127112 100644
--- a/ref-tests/tests/integration.rs
+++ b/ref-tests/tests/integration.rs
@@ -191,12 +191,12 @@ fn canister_reject_call() {
                 Err(AgentError::CertifiedReject(RejectResponse {
                     reject_code: RejectCode::CanisterError,
                     reject_message,
-                    error_code: None,
+                    error_code: Some(error_code),
                     ..
                 })) if reject_message.contains(&format!(
                     "Canister {}: Canister has no update method 'wallet_send'",
                     alice.canister_id()
-                ))
+                )) && error_code == "IC0536"
             ),
             "wrong error: {result:?}"
         );