dbase_open error on deleting rows from remote file - php

Question

I hope you can help me with my problem.
I have a local site that reads data from DBF files on a terminal within the network. So what I did, I shared the DBF files on a PC running Windows XP, with full read/write permission.
When the PHP script is run on the Ubuntu server, it will first ping the PC on the network. After confirming that it is connected, it will mount the shared files within the server. Please note that the directory /mnt has 777 permissions and it is set to subdirectories as well. The owner is also www-data which is the user for PHP.
The script is able to read the data from the DBF files using this setup. I use the below script to read the data from the dbf file:
$db1 = dbase_open("/mnt/test.dbf", 0) or die(mysql_error());
for($counter=1;$counter<=dbase_numrecords($db1);$counter++){
$dbf_data = dbase_get_record_with_names($db1, $counter) or die(mysql_error());
// insert data to MYSQL database
}
The script above works, but only for reading the data. When I change to:
dbase_open("/mnt/test.dbf", 2)
it should have read and write access, However it does not let me remove the rows that were already read. I use:
for($count=1;$count<=dbase_numrecords($db1);$count++){
dbase_delete_record($db1, $count);
}
dbase_pack($db1);
but it doesnt work. I also tried to put dbase_pack inside the loop, but still the same. Here is a screenshot of the error:
Hope you can help. Thanks in advance!