Tablespace files dropped automatically.

Hi,

I am Using PostgreSQL 8.4 along with Slony-I replication in windows XP.
A client application continuously updating data to the database.

In my database some tables are in default database and some tables are
in another tables. My issue is that after a moth's running, some of the
files in the 16384 folder of the external table space get deleted
automatically. Now an error message is showing in pgAdmin saying that
"could not open relation pg_tblspc/16385/16384/16783: No such file or
directory."

What is the reason for this?

Is the tablespace files are dropped automatically?

In which condition, the table space files get deleted? What is the
reason ? and What is the Possible solution.

Thanks & Regards,

Vishnu S

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