diff --git a/kordophone/Bridge/Operations/MBIMFetchAttachmentOperation.m b/kordophone/Bridge/Operations/MBIMFetchAttachmentOperation.m
index a21433f..1822d70 100644
--- a/kordophone/Bridge/Operations/MBIMFetchAttachmentOperation.m
+++ b/kordophone/Bridge/Operations/MBIMFetchAttachmentOperation.m
@@ -76,10 +76,13 @@
                     break;
                 }
                 
+                // Convert to JPEG.
                 responseData = MBIMCGImageJPEGRepresentation(previewImage);
                 
                 // Persist JPEG preview to disk
-                [responseData writeToURL:previewURL atomically:YES];
+                if (previewURL) {
+                    [responseData writeToURL:previewURL atomically:YES];
+                }
             } else {
                 // File exists
                 MBIMLogInfo(@"Using cached preview image for guid: %@ at %@", guid, [previewURL path]);