Re-install FS04

[runibl]

First backup you FsPassengers/Database folder (Important). Or even better backup the entire FsPassengers folder, as you already did it seems.
Next uninstall everything as usually.

Then install FS2004. And after that install FsPassengers using the FsP install file.

After FsP is installed, copy the files from the Database folder that you backed up before, and put them in to the database folder in the newly
installed FsPassengers.
(You can also copy files from the config folder (settings), and payload_model folder (Payloads, if you added any)).

Then start up FS2004, create a flight as normal, go to the FsP menu and register FsP.
Now everything should be good.