Can find some extensions but not all

Even though I have all the extensions in the same directory I keep getting the error that such and such extension can't be found. Here is the list of ones that cant be found but are in the same directory as the rest: php_ifx.dll php_ingres.dll php_oci8.dll php_oracle.dll php_sybase_ct.dll Here is a list of ones that I would like to get copies of: php_iisfunc.dll php_mcrypt.dll php_printer.dll php_sablot.dll Thanks for any help.