cannot import

Hey,

Ive been trying to create my site using wordpress on a server space i bought, and ive had a few issues and had to start over again numerous times.

I think it came down to a plug in, but wordpress could not see images in the media file, nor would it show them,

anyway, i am trying to make a duplicate of my site just incase anything happens again, so ive exported my site from within wordpress, but everytime i try to import it onto another installation, all i get is this error message.

Warning: set_time_limit() [function.set-time-limit]: Cannot set time limit in safe mode in /home/sdbphot1/public_html/duplicate1/wp-content/plugins/wordpress-importer/wordpress-importer.php on line 91

i have tried it on many installations, and from many export files, it then fails to import any media from my last site.

any ideas why this is happening?

thanks,