diff --git a/src/copy.ts b/src/copy.ts
index 12d14df9..fb9985a2 100644
--- a/src/copy.ts
+++ b/src/copy.ts
@@ -143,7 +143,7 @@ function copySrcToDest(context: BuildContext, src: string, dest: string, filter:
 
     fs.copy(src, dest, opts, (err) => {
       if (err) {
-        if (err.message.indexOf('ENOENT') > -1) {
+        if (err.message && err.message.indexOf('ENOENT') > -1) {
           resolve({ success: false, src: src, dest: dest, errorMessage: `Error copying "${src}" to "${dest}": File not found`});
         } else {
           resolve({ success: false, src: src, dest: dest, errorMessage: `Error copying "${src}" to "${dest}"`});