That's because you're not using the installer. You did not write a version of IB. When you do something manually, it's good to be prepared for such surprises. You can search for a program that tells you the dependencies of gds32.dll. They are mostly on MS runtimes. In your case, maybe just copying msvcr120.dll would help, but that depends on the version and installed packages of Windows. You should also look at the log of the Windows programs, it also sometimes says which package is missing. In addition to these dlls, it is good to put an interbase.msg file... In general, either install the IB client or copy these files to the folder of your program. Because you may have a problem with different client versions for IB or Firebird, for example, on this computer