diff --git a/tsdb/fileutil/mmap_windows.go b/tsdb/fileutil/mmap_windows.go
index b942264123..5704b3b96d 100644
--- a/tsdb/fileutil/mmap_windows.go
+++ b/tsdb/fileutil/mmap_windows.go
@@ -27,14 +27,15 @@ func mmap(f *os.File, size int) ([]byte, error) {
 	}
 
 	addr, errno := syscall.MapViewOfFile(h, syscall.FILE_MAP_READ, 0, 0, uintptr(size))
-	if addr == 0 {
-		return nil, os.NewSyscallError("MapViewOfFile", errno)
-	}
 
 	if err := syscall.CloseHandle(syscall.Handle(h)); err != nil {
 		return nil, os.NewSyscallError("CloseHandle", err)
 	}
 
+	if addr == 0 {
+		return nil, os.NewSyscallError("MapViewOfFile", errno)
+	}
+
 	return (*[maxMapSize]byte)(unsafe.Pointer(addr))[:size], nil
 }