Liviuslivius:
As per Frank Schlottmann's response: "Your application directory should contain the following Firebird directories lib intl plugins and the following files: fbclient.dll firebird.msg ibutil.dll icudt63.dll icudt63l.dat icuin63.dll icuuc63.dll" But as he mentioned he's using Firebird 4 beta and for example icudt63.dll is icudt53.dll in Firebird 3; just in case I was missing something I copied the contents of the Firebird zip kit to my applications Debug directory including any subdirectories located in the Firebird directory; I did delete Firebird.exe since the documentation says it's not necessary for embedded. Here's a directory listing of my Debug directory minus any Delphi dcu files: Volume in drive I is Data Volume Serial Number is A327-5FF0 Directory of I:\Delphi\Test-Embedded\Win64\Debug 04/24/2019 11:47 AM <DIR> . 04/24/2019 11:47 AM <DIR> .. 05/07/2017 11:45 PM 170 Attributes.txt 05/07/2017 11:45 PM 170 Categorys.txt 01/28/2019 07:57 PM 2,293,760 ComTestEm.FDB 10/03/2018 02:46 PM 7,053,824 engine12.dll 04/23/2019 08:01 PM 11,917 EntVarInfoP.dcu 03/27/2015 11:40 AM 876,032 fbclient.dll 10/03/2018 02:47 PM 285,184 fbguard.exe 10/03/2018 02:46 PM 314,880 fbsvcmgr.exe 10/03/2018 02:41 PM 634,880 fbtrace.dll 10/03/2018 02:47 PM 307,712 fbtracemgr.exe 10/03/2018 02:47 PM 303,616 fb_lock_print.exe 04/23/2019 11:36 PM 32,897 firebird.conf 10/03/2018 02:46 PM 149,648 firebird.msg 10/03/2018 02:47 PM 700,416 gbak.exe 10/03/2018 02:47 PM 327,168 gfix.exe 10/03/2018 02:45 PM 878,592 gpre.exe 10/03/2018 02:47 PM 352,768 gsec.exe 10/03/2018 02:47 PM 270,848 gsplit.exe 10/03/2018 02:47 PM 332,288 gstat.exe 10/03/2018 02:40 PM 8,192 ib_util.dll 02/20/2014 05:09 AM 3,072 icudt52.dll 01/12/2016 09:31 PM 5,616,608 icudt52l.dat 10/05/2013 12:22 AM 1,707,520 icuin52.dll 10/05/2013 12:20 AM 1,293,824 icuuc52.dll 07/09/2003 01:59 AM 26,519 IDPLicense.txt 11/12/2015 10:19 AM 410 install_service.bat 10/03/2018 02:46 PM 19,456 instclient.exe 10/03/2018 02:47 PM 12,288 instreg.exe 10/03/2018 02:46 PM 272,384 instsvc.exe 04/23/2019 05:11 PM <DIR> intl 07/09/2003 01:59 AM 24,405 IPLicense.txt 10/03/2018 02:46 PM 641,536 isql.exe 04/23/2019 05:11 PM <DIR> lib 03/18/2010 11:36 AM 607,568 msvcp100.dll 03/18/2010 11:36 AM 827,728 msvcr100.dll 10/03/2018 02:46 PM 329,216 nbackup.exe 04/23/2019 11:37 PM <DIR> plugins 10/03/2018 02:46 PM 566,272 qli.exe 10/03/2018 03:17 PM 1,991 Readme.txt 10/03/2018 02:46 PM 1,605,632 security3.fdb 02/11/2019 10:10 PM 46 server.ini 06/01/2018 11:00 PM 22 Thumbs.ini 10/03/2018 02:47 PM 386,048 udr_engine.dll 11/10/2015 12:08 PM 273 uninstall_service.bat 12/01/2014 10:44 AM 77,824 zlib1.dll My application is set to be compiled as 64bit and I'm using the x64 Firebird kit; you mention "Firebird files should be in the same dir as your exe with folder structure e.g /providers and /udf if you use" I can't find any reference to a "providers" or "udf" directory, they're not in the Firebird kit and the https://www.ibphoenix.com/files/Embedded_fb3.pdf document doesn't mention them. Also as someone else suggested, I tried running the application directly outside of the IDE and I still the error "[FireDAC]{Phys][FB]unavailable database".
