diff --git a/uk/ac/sanger/artemis/components/variant/IOUtils.java b/uk/ac/sanger/artemis/components/variant/IOUtils.java
index bb8e009fad0bc48f914213b662446ee2a314922f..dace8e28bdbd2be77471e10c96245223f1892b12 100644
--- a/uk/ac/sanger/artemis/components/variant/IOUtils.java
+++ b/uk/ac/sanger/artemis/components/variant/IOUtils.java
@@ -296,6 +296,8 @@ class IOUtils
       if(!view)
       {
         File f = getFile(vcfReaders[0].getFileName(), 1, suffix, yBox);
+        if(f == null)
+          return;
         writer = new FileWriter(f);
         fastaFiles += f.getAbsolutePath()+"\n";
       }