diff --git a/Source/mpqapi.cpp b/Source/mpqapi.cpp
index a876342c8..039f9721b 100644
--- a/Source/mpqapi.cpp
+++ b/Source/mpqapi.cpp
@@ -207,6 +207,7 @@ struct Archive {
 			}
 		} else {
 			mode |= std::ios::trunc;
+			this->size = 0;
 		}
 		if (!stream.Open(name, mode)) {
 			stream.Close();