diff --git a/config/scheduled_analysis.toml b/config/scheduled_analysis.toml
index 226ba156..110fb75c 100644
--- a/config/scheduled_analysis.toml
+++ b/config/scheduled_analysis.toml
@@ -1,5 +1,5 @@
 [run]
-tickers = ["GOOGL", "NVDA", "TSM", "APPL", "ETN", "LLY", "GLDM", "VRT", "TSLA", "GEV", "VXUS", "RSP", "FANG", "ETHU", "ORCL", "MU"]
+tickers = ["GOOGL", "NVDA", "TSM", "AAPL", "ETN", "LLY", "GLDM", "VRT", "TSLA", "GEV", "VXUS", "RSP", "FANG", "ETHU", "ORCL", "MU"]
 analysts = ["market", "social", "news", "fundamentals"]
 output_language = "Korean"
 trade_date_mode = "latest_available"
diff --git a/tradingagents/scheduled/runner.py b/tradingagents/scheduled/runner.py
index ebac3d63..1a69fcc2 100644
--- a/tradingagents/scheduled/runner.py
+++ b/tradingagents/scheduled/runner.py
@@ -131,14 +131,22 @@ def resolve_trade_date(
     if mode == "previous_business_day":
         return _previous_business_day(now.date()).isoformat()
 
+    if not _looks_like_yahoo_ticker_format(normalized_symbol):
+        raise RuntimeError(
+            f"Could not resolve the latest available trade date for {ticker} ({normalized_symbol}); "
+            f"symbol format looks invalid for Yahoo Finance. Expected examples: AAPL, BRK.B, 005930.KS."
+        )
+
     history = yf.Ticker(normalized_symbol).history(
         period=f"{config.run.latest_market_data_lookback_days}d",
         interval="1d",
         auto_adjust=False,
     )
     if history.empty:
+        symbol_hint = _ticker_hint(normalized_symbol)
         raise RuntimeError(
-            f"Could not resolve the latest available trade date for {ticker} ({normalized_symbol}); yfinance returned no rows."
+            f"Could not resolve the latest available trade date for {ticker} ({normalized_symbol}); "
+            f"yfinance returned no rows.{symbol_hint}"
         )
 
     last_index = history.index[-1]
@@ -149,6 +157,30 @@ def resolve_trade_date(
     return last_date.isoformat()
 
 
+def _looks_like_yahoo_ticker_format(symbol: str) -> bool:
+    if not symbol:
+        return False
+    if symbol.count(".") > 1:
+        return False
+    if symbol[0] == "." or symbol[-1] == ".":
+        return False
+    for ch in symbol:
+        if not (ch.isalnum() or ch in ".-"):
+            return False
+    return True
+
+
+def _ticker_hint(symbol: str) -> str:
+    normalized = symbol.upper()
+    common_typos = {
+        "APPL": " APPL is likely an invalid ticker; if you intended Apple, use 'AAPL'.",
+    }
+    return common_typos.get(
+        normalized,
+        " The symbol may be wrong (typo or delisted) or currently unavailable on Yahoo Finance.",
+    )
+
+
 def _run_single_ticker(
     *,
     config: ScheduledAnalysisConfig,