Here is some new information regarding this problem:
- I now have a Windows 7 Professional 32 bit PC which has the same problem
- The problem also occurs if I install Firebird to another directory
- The problem also occurs if I run the Firebird Server under a normal user
- The problem also occurs when using Firebird 2.5 RC2
- The problem also occurs if I a define an alias for security2.fdb as Helen proposed

And, may be, the most important information:
The problem only occurs if using TCP/IP.
gsec -user SYSDBA -pass masterkey -database "c:\program files\firebird\firebird_2_1\security2.fdb" -display > out.txt
is okay but
gsec -user SYSDBA -pass masterkey -database "localhost:c:\program files\firebird\firebird_2_1\security2.fdb" -display > out.txt
creates an empty file out.txt

Can you reproduce it using localhost?