Hi,
My version of MSS is 1.15. The problem is happening when i open excel file strict from the mounted hdd, and after changing this file when i'm trying to save (ctrl+s) on this same hdd size of the file is changing to 0 bits. This same is happening to movie files, when i'm trying watch them strict from the mounted hdd the size of files are changing to 0 bits.
For mounting hdd on my terminal i'm using SFTP Net Drive(windows) and i do not have any error logs on the server (debian).

<Default>
        GlobalDownload          0       #total speed download for all clients
        # o -> bytes   k -> kilo bytes   m -> mega bytes
        GlobalUpload            0       #total speed download for all clients ($
        LimitConnection         20      #max connection for the server sftp
        LimitConnectionByUser   1       #max connection for the account
        LimitConnectionByIP     10       #max connection by ip for the account
        StayAtHome              true    #limit client to his home
        VirtualChroot           true    #fake a chroot to the home account
        Home                    /opt/users/$USER     #overrite home of the user$
        HideFiles               "^(lost\+found|public_html)$"   #Hide file/direc$
        HideNoAccess            true    #Hide file/directory which user has no $
        IgnoreHidden            true    #treat all hidden files as if they don'$
        IdleTimeOut             300     #(in second) deconnect client is idle t$
#        ResolveIP               true    #resolve ip to dns
        DefaultRights                   700 700       #Set default rights for$
        ShowLinksAsLinks        true   #show links as their destinations
        ConnectionMaxLife       1d      #limits connection lifetime to 1 day
        Charset                 "UTF-8"   #set charset of computer
        DefaultRights = 770 770
        LogFile                 /var/log/sftp_server.log
</Default>

sshd_config

AuthorizedKeysFile      /opt/keys/%u/.ssh/authorized_keys
Subsystem sftp /usr/lib/openssh/sftp-server -l DEBUG

#################################################
#        MySecureShell Verification Tool        #
#################################################

** Verifing file existance **

Verifing file existance of /bin/MySecureShell                   [ OK ]
Verifing file existance of /usr/bin/sftp-who                    [ OK ]
Verifing file existance of /usr/bin/sftp-kill                   [ OK ]
Verifing file existance of /usr/bin/sftp-state                  [ OK ]
Verifing file existance of /usr/bin/sftp-admin                  [ OK ]
Verifing file existance of /usr/bin/sftp-verif                  [ OK ]
Verifing file existance of /usr/bin/sftp-user                   [ OK ]
Verifing file existance of /etc/ssh/sftp_config                 [ OK ]

** Verifing rights **

Verifing file rights of /etc/ssh/sftp_config                    [ OK ]
Verifing file rights of /usr/bin/sftp-who                       [ OK ]
Verifing file rights of /usr/bin/sftp-verif                     [ OK ]
Verifing file rights of /usr/bin/sftp-user                      [ OK ]
Verifing file rights of /usr/bin/sftp-kill                      [ OK ]
Verifing file rights of /usr/bin/sftp-state                     [ OK ]
Verifing file rights of /usr/bin/sftp-admin                     [ OK ]
Verifing file rights of /bin/MySecureShell                      [ OK ]

** Verifing rotation logs **

MySecureShell rotation logs                                     [ OK ]

** Verifing server status **

Verifing server status (ONLINE)                                 [ OK ]

Any suggestions, advice
pls help