diff --git a/backend/app/routers/system.py b/backend/app/routers/system.py
index 72cfa86..35f0aba 100644
--- a/backend/app/routers/system.py
+++ b/backend/app/routers/system.py
@@ -295,8 +295,11 @@ def test_jira_connection(
 
     try:
         jira = get_user_jira_client(current_user, db)
-        # Lightweight call: get current user info (10 s hard timeout)
-        jira._session.timeout = 10  # type: ignore[attr-defined]
+        # 10-second timeout so we never block Cloudflare into a 524
+        try:
+            jira._session.timeout = 10  # type: ignore[attr-defined]
+        except Exception:
+            pass
         myself = jira.myself()
         return {
             "status": "ok",
@@ -305,21 +308,26 @@ def test_jira_connection(
         }
     except Exception as exc:
         err = str(exc)
-        # Translate common Atlassian-library errors into human-readable messages
+        # Always return HTTP 200 with status="error" so Cloudflare never
+        # intercepts the response and the frontend always sees our message.
         if "Expecting value" in err or "line 1 column 1" in err:
-            detail = (
-                "Jira returned an unexpected response — check that the URL is correct "
-                "and that the account email + API token are valid."
+            msg = (
+                "Jira returned a non-JSON response. "
+                "Verify the URL (e.g. https://company.atlassian.net), "
+                "email and API token."
             )
         elif "401" in err or "Unauthorized" in err:
-            detail = "Authentication failed (401). Verify your Atlassian email and API token."
+            msg = "Authentication failed (401). Check your Atlassian email and API token."
         elif "403" in err or "Forbidden" in err:
-            detail = "Access denied (403). The token may not have permission to access this Jira instance."
+            msg = "Access denied (403). The token may not have permission for this Jira project."
         elif "timed out" in err.lower() or "timeout" in err.lower():
-            detail = "Connection timed out. Check the Jira URL is reachable from the server."
+            msg = "Connection timed out. Check that the Jira URL is reachable from the server."
+        elif "not configured" in err.lower():
+            msg = err
         else:
-            detail = f"Jira connection failed: {err}"
-        raise HTTPException(status_code=502, detail=detail)
+            msg = f"Jira connection failed: {err}"
+        logger.warning("Jira test connection failed: %s", err)
+        return {"status": "error", "message": msg, "jira_url": jira_url}
 
 
 # ---------------------------------------------------------------------------
diff --git a/backend/app/services/jira_service.py b/backend/app/services/jira_service.py
index c040a3c..2b81ebc 100644
--- a/backend/app/services/jira_service.py
+++ b/backend/app/services/jira_service.py
@@ -142,8 +142,12 @@ def get_user_jira_client(user: User, db: Session):
 
     from atlassian import Jira
 
+    # Strip trailing slash — the Atlassian library appends paths like
+    # /rest/api/2/myself and a trailing slash causes double-slash URLs.
+    clean_url = jira_url.rstrip("/")
+
     return Jira(
-        url=jira_url,
+        url=clean_url,
         username=auth_email,
         password=user.jira_api_token,
         cloud=True,
diff --git a/frontend/src/api/settings.ts b/frontend/src/api/settings.ts
index ff4d185..3cf9532 100644
--- a/frontend/src/api/settings.ts
+++ b/frontend/src/api/settings.ts
@@ -178,7 +178,12 @@ export async function updateJiraConfig(payload: JiraConfigUpdate): Promise<JiraC
   return data;
 }
 
-export async function testJiraConnection(): Promise<{ status: string; connected_as: string; jira_url: string }> {
+export async function testJiraConnection(): Promise<{
+  status: "ok" | "error";
+  connected_as?: string;
+  jira_url?: string;
+  message?: string;
+}> {
   const { data } = await client.post("/system/jira-test");
   return data;
 }
diff --git a/frontend/src/pages/SettingsPage.tsx b/frontend/src/pages/SettingsPage.tsx
index 5c5029f..0ee55ea 100644
--- a/frontend/src/pages/SettingsPage.tsx
+++ b/frontend/src/pages/SettingsPage.tsx
@@ -1046,8 +1046,14 @@ function JiraConfigSection() {
   const testMut = useMutation({
     mutationFn: testJiraConnection,
     onSuccess: (data) => {
-      setTestResult({ connectedAs: data.connected_as, url: data.jira_url });
-      setTestError(null);
+      // Backend always returns HTTP 200; status field tells us if it worked
+      if (data.status === "ok") {
+        setTestResult({ connectedAs: data.connected_as ?? "", url: data.jira_url ?? "" });
+        setTestError(null);
+      } else {
+        setTestError((data as { message?: string }).message ?? "Connection failed");
+        setTestResult(null);
+      }
     },
     onError: (err: Error) => {
       setTestError(err.message || "Connection failed");