diff --git a/thunderbirdparser/src/org/sleuthkit/autopsy/thunderbirdparser/PstParser.java b/thunderbirdparser/src/org/sleuthkit/autopsy/thunderbirdparser/PstParser.java
index af3c55bf8f..350ee6df6a 100755
--- a/thunderbirdparser/src/org/sleuthkit/autopsy/thunderbirdparser/PstParser.java
+++ b/thunderbirdparser/src/org/sleuthkit/autopsy/thunderbirdparser/PstParser.java
@@ -254,10 +254,16 @@ class PstParser {
             int bufferSize = 8176;
             byte[] buffer = new byte[bufferSize];
             int count = attachmentStream.read(buffer);
+            
+            if(count == -1) {
+                throw new IOException("attachmentStream invalid (read() fails). File "+attach.getLongFilename()+ " skipped");
+            }
+            
             while (count == bufferSize) {
                 out.write(buffer);
                 count = attachmentStream.read(buffer);
             }
+
             byte[] endBuffer = new byte[count];
             System.arraycopy(buffer, 0, endBuffer, 0, count);
             out.write(endBuffer);