What does the script actually do? It may be possible to seek more specific help from forum members if you could provide more details.
allow_url_fopen was disabled for security reasons, and the decision was not taken lightly. You can very easily compile your own version of PHP that has the directive enabled (see the wiki for more details on that), but it would be better to adapt your script to do without it. If you need access to remote websites (sites other than your own), using cURL will do the trick.
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