diff --git a/src/com/hippo/ehviewer/ehclient/ExDownloader.java b/src/com/hippo/ehviewer/ehclient/ExDownloader.java
index e87c3d5a3..431508ce6 100644
--- a/src/com/hippo/ehviewer/ehclient/ExDownloader.java
+++ b/src/com/hippo/ehviewer/ehclient/ExDownloader.java
@@ -248,7 +248,7 @@ public class ExDownloader implements Runnable {
         if (mImageNum != -1) {
             return mImageNum - 1;
         } else {
-            return Math.max(Math.max(Math.max(mStartIndex - 1,
+            return Math.max(Math.max(Math.max(mStartIndex,
                     Math.max(mCurMaxPreviewPage, mPreviewPageNum - 1) * mPreviewPerPage),
                     mPageTokeArray.maxValidIndex()), 0);
         }