diff --git a/src/main/java/org/ids_mannheim/TotalNGram.java b/src/main/java/org/ids_mannheim/TotalNGram.java
index 949d7ab..992b03c 100644
--- a/src/main/java/org/ids_mannheim/TotalNGram.java
+++ b/src/main/java/org/ids_mannheim/TotalNGram.java
@@ -1,16 +1,19 @@
 package org.ids_mannheim;
 
+import picocli.CommandLine;
+
 import java.io.File;
-import java.io.FileNotFoundException;
 import java.io.PrintStream;
+import java.nio.file.AccessDeniedException;
+import java.nio.file.FileAlreadyExistsException;
+import java.nio.file.Files;
+import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.concurrent.*;
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
 
-import picocli.CommandLine;
-
 @CommandLine.Command(mixinStandardHelpOptions = true,
         name = "totalngram", description = "add ngram counts from KorAP-XML or CoNLL-U files")
 
@@ -24,8 +27,12 @@
 
     @SuppressWarnings("CanBeFinal")
     @CommandLine.Option(names = {"-o",
-            "--output-file"}, description = "Output file (default: -")
-    File output_file = null;
+            "--output-file"}, description = "Output file (default: ${DEFAULT-VALUE})")
+    String output_fillename = "-";
+
+    @SuppressWarnings("CanBeFinal")
+    @CommandLine.Option(names = {"--force"}, description = "Force overwrrite (default: ${DEFAULT-VALUE})")
+    boolean force_overwrite = false;
 
     @SuppressWarnings("CanBeFinal")
     @CommandLine.Option(names = {"-P",
@@ -50,7 +57,24 @@
 
     @Override
     public Integer call() throws Exception {
-        PrintStream output_stream = (output_file == null || output_file.equals("-") ? System.out : new PrintStream(output_file));
+        PrintStream output_stream;
+        if ((output_fillename == null) || output_fillename.equals("-")) {
+            output_stream = System.out;
+        } else {
+            File f = new File(output_fillename);
+            try {
+                Files.createFile(f.toPath());
+            } catch (AccessDeniedException e) {
+                System.err.println("ERROR: Cannot write output file '" + output_fillename + "'");
+                System.exit(-1);
+            } catch (FileAlreadyExistsException e) {
+                if (!force_overwrite) {
+                    System.err.println("ERROR: '" + output_fillename + "' already exits. Use --force to overwrite.");
+                    System.exit(-1);
+                }
+            }
+            output_stream = new PrintStream(f);
+        }
 
         FoldedEntry.setFolds(FOLDS);
         ConcurrentHashMap<String, FoldedEntry> map = new ConcurrentHashMap<>();
@@ -83,7 +107,7 @@
         return null;
     }
 
-    public static void main(String[] args) throws FileNotFoundException {
+    public static void main(String[] args) {
         System.exit(new CommandLine(new TotalNGram()).execute(args));
     }
 }