diff --git a/BTDB/StreamLayer/MemoryMappedMemReader.cs b/BTDB/StreamLayer/MemoryMappedMemReader.cs
index 9466f2c7..629b7989 100644
--- a/BTDB/StreamLayer/MemoryMappedMemReader.cs
+++ b/BTDB/StreamLayer/MemoryMappedMemReader.cs
@@ -82,9 +82,9 @@ public bool Eof(ref MemReader memReader)
 
     public void Dispose()
     {
-        _viewAccessor.SafeMemoryMappedViewHandle.ReleasePointer();
-        _memoryMappedFile.Dispose();
-        _fileHandle.Dispose();
+        _viewAccessor?.SafeMemoryMappedViewHandle.ReleasePointer();
+        _memoryMappedFile?.Dispose();
+        _fileHandle?.Dispose();
         GC.SuppressFinalize(this);
     }