“Access to rfunc.dll is denied by system administrator” Solution 

While the Firebird database is usually reliable, there are some errors that crop up from time to time. Have you ever had this one? 

This normally means that the rfunc.dll file can’t be found by Firebird. This can usually be rectified by downloading the rfunc.dll file from SourceForge and placing it directly into the UDP folder of your Firebird install.