diff --git a/src/core/copyjob.cpp b/src/core/copyjob.cpp
--- a/src/core/copyjob.cpp
+++ b/src/core/copyjob.cpp
@@ -1637,7 +1637,9 @@
             it = files.erase(it);
         }
 
-        if ((*it).size > ((1ul << 32) - 1)) { // ((1ul << 32) - 1) = 4 GB
+        // if _all_ elements in "files" have been skipped, the last files.erase() will return
+        // files.end(), bug 408350
+        if (it != files.end() && (*it).size > ((1ul << 32) - 1)) { // ((1ul << 32) - 1) = 4 GB
             const auto fileSystem = KFileSystemType::fileSystemType(m_globalDest.toLocalFile());
             if (fileSystem == KFileSystemType::Fat) {
                 q->setError(ERR_FILE_TOO_LARGE_FOR_FAT32);