Why can't I connect to a local (foreign) .fdb file even with a password?

Question

SQL

There is a desktop program, it works with data, and stores them in a .fdb file (embedded firebird) and we drag this database along with the program. When opening the program, you must enter Login: Username and Password: Password to open the database. Opens with the program. But I can't open the same .fdb file via
> isql -u Username -p Password example.fdb
Error: Your user name and password are not defined. Ask your database administrator to set up a Firebird login.
If you enter:
> isql -u sysdba -p masterkey example.fdb
Error: Statement failed, SQLSTATE = HY000
file D:\PROGRAMMA\EXAMPLE.FDB is not a valid database
Question: How can I open someone else's .fdb file (via isql)?
PS When working with the program, the Internet is not required.

Answer 1

Found the solution myself. I had to uninstall Firebird for 64 bit and install Firebird for 32 bit. It turns out that the database file created in Firebird 32 bit cannot be opened in Firebird 64 bit.

Answer 2

is not a valid database

Probably a broken file.

Answer 3

Opens with the program. But I can't open the same .fdb file via
> isql -u Username -p Password example.fdb

The password in the program can be changed to access the database.