diff --git a/routers/repo/attachment.go b/routers/repo/attachment.go
index e2b6f4d2b..c2bbc5d46 100755
--- a/routers/repo/attachment.go
+++ b/routers/repo/attachment.go
@@ -398,6 +398,20 @@ func GetSuccessChunks(ctx *context.Context) {
 		attachID = attach.ID
 	}
 
+	if attach == nil {
+		ctx.JSON(200, map[string]string{
+			"uuid":     fileChunk.UUID,
+			"uploaded": strconv.Itoa(fileChunk.IsUploaded),
+			"uploadID": fileChunk.UploadID,
+			"chunks":   string(chunks),
+			"attachID": "0",
+			"datasetID": "0",
+			"fileName": "",
+			"datasetName": "",
+		})
+		return
+	}
+
 	dataset, err := models.GetDatasetByID(attach.DatasetID)
 	if err != nil {
 		ctx.ServerError("GetDatasetByID", err)