ftp functions are not working however ftp option ini phpini is enable at my server.it showing error like:
Warning: ftp_chdir() [function.ftp-chdir]: Can't change directory to /home/dont/public_html: No such file or directory in /home/dont/public_html/upload/engine.php on line 327
Sounds like you're just using the FTP functions incorrectly, but we'd need a code example to be sure. Such as what's around line 327 on engine.php...
As DOOManiac says, there's not much we can do without seeing the rest of your code.
The most likely problem here is that your FTP root dir isn't your server's root dir. You may need to change directory to /public_html instead of /home/dont/public_html