diff --git a/annotation/src/main/java/lcsb/mapviewer/annotation/cache/BigFileCache.java b/annotation/src/main/java/lcsb/mapviewer/annotation/cache/BigFileCache.java
index c81f8cf544c97a843ed3f687c01e9cc7bed56cbe..e9c8b39fe04a9785e7da817d1317f74a54979ba5 100644
--- a/annotation/src/main/java/lcsb/mapviewer/annotation/cache/BigFileCache.java
+++ b/annotation/src/main/java/lcsb/mapviewer/annotation/cache/BigFileCache.java
@@ -848,6 +848,10 @@ public class BigFileCache {
         logger.warn("File is supposed to be cached but it's not there... " + sourceUrl);
         return false;
       }
+      if (entry.getDownloadProgress() == null || entry.getDownloadProgress() < 100.0) {
+        logger.warn("File is not complete: " + entry.getLocalPath() + ".");
+        return false;
+      }
     }
     return entry != null;
   }