The refbase PHP scripts will only work correctly if the following settings are present within your PHP configuration file (php.ini):

allow_url_fopenOn(only required for the "Import IDs" feature, e.g. import from PMID or DOI)
magic_quotes_gpcOn(only necessary for versions prior to refbase-0.9.0)

("1" is equivalent to "On")

Note that export to BibTeX, Endote or RIS (via Bibutils) uses the exec() function. I.e., if safe_mode is set to On in php.ini then you'll need to put the Bibutils programs within the directory that's specified in safe_mode_exec_dir.

Additionally, be sure you've set the values for the directives post_max_size and upload_max_filesize to be large enough to handle your uploads. If you're experiencing script execution timeouts, you may want to increase the values for max_execution_time, max_input_time and memory_limit. As a general rule, memory_limit should be substantially greater than post_max_size which, in turn, should be greater than upload_max_filesize.

You'll need to restart your web server to apply any changes you've made.

How to locate your active php.ini file

Check your PHP documentation for the location of the php.ini file. Its location depends on the platform and PHP version you're using. Alternatively, you can call the phpinfo() function which will tell you the location of this file. To call this function, simply put the string

<?php phpinfo() ?>

into a .php file within your web directory and access this file via your browser.