Access to VirtualBox host system folders from guest ReactOS

I run ReactOS under VBox. Network adapter bridged, so ReactOS is in the same network as Host system. VBox additions installed. Some folders from host system are shared with host system itself and some with VBox. ReactOS can't see any network places.

• Network places looks dead, no reaction after long time.
• \\\192.168.xx.xx in explorer has no effect. (two \, not 3)
• ping is good to any local or inet address.
• explorer can open pages.

ReactOS becomes unuseful and unusable while user cannot exchange files.