1 files changed, 4 insertions, 0 deletions
diff --git a/core/Archive/ArchiveInvalidator.php b/core/Archive/ArchiveInvalidator.php
index 68274c9857..ad449921f2 100644
--- a/core/Archive/ArchiveInvalidator.php
+++ b/core/Archive/ArchiveInvalidator.php
@@ -147,6 +147,10 @@ class ArchiveInvalidator
             $siteId = (int) $report[0];
             $date   = $report[1];
 
+            if (empty($siteId)) {
+                continue;
+            }
+
             if (empty($sitesPerDay[$date])) {
                 $sitesPerDay[$date] = array();
             }