diff --git a/freqtrade/optimize/__init__.py b/freqtrade/optimize/__init__.py
index 168481920..ab7a6be43 100644
--- a/freqtrade/optimize/__init__.py
+++ b/freqtrade/optimize/__init__.py
@@ -29,7 +29,7 @@ def trim_tickerlist(tickerlist: List[Dict], timerange: Tuple[Tuple, int, int]) -
     if stype[0] == 'index':
         start_index = start
     elif stype[0] == 'date':
-        while tickerlist[start_index][0] < start * 1000:
+        while start_index < len(tickerlist) and tickerlist[start_index][0] < start * 1000:
             start_index += 1
 
     if stype[1] == 'line':
@@ -37,7 +37,7 @@ def trim_tickerlist(tickerlist: List[Dict], timerange: Tuple[Tuple, int, int]) -
     if stype[1] == 'index':
         stop_index = stop
     elif stype[1] == 'date':
-        while tickerlist[stop_index-1][0] > stop * 1000:
+        while stop_index > 0 and tickerlist[stop_index-1][0] > stop * 1000:
             stop_index -= 1
 
     if start_index > stop_index:
@@ -100,15 +100,11 @@ def load_data(datadir: str,
 
     for pair in _pairs:
         pairdata = load_tickerdata_file(datadir, pair, ticker_interval, timerange=timerange)
-        if not pairdata:
-            # download the tickerdata from exchange
-            download_backtesting_testdata(datadir,
-                                          pair=pair,
-                                          tick_interval=ticker_interval,
-                                          timerange=timerange)
-            # and retry reading the pair
-            pairdata = load_tickerdata_file(datadir, pair, ticker_interval, timerange=timerange)
-        result[pair] = pairdata
+        if pairdata:
+            result[pair] = pairdata
+        else:
+            logger.warn('No data for pair %s, use --update-pairs-cached to download the data', pair)
+        
     return result