If IDEInstaller cannot find Delphi...

[Sergey Tkachenko]

If IDEInstaller (our setup application that installs components in Delphi and C++Builder IDE) does not list your version of Delphi/C++Builder, most probably, RAD Studio is misconfigured.

The first thing to check is registry entries.
Open RegEdit (WinKey + R, type "regedit", press Enter).
Find the key for your RAD Studio version.
For Delphi 10.3, it is HKEY_CURRENT_USER\Software\Embarcadero\BDS\20.0
For Delphi 10.2, it is HKEY_CURRENT_USER\Software\Embarcadero\BDS\19.0
and so on. (for older versions of RAD Studio, the key name includes "CodeGear" or "Borland" instead of "Embarcadero").
Check "RootDir" and "App" entries. They must contain a correct path to RAD Studio and a correct full path to bds.exe.
If they are not correct, fix them.

The second thing to check is rsvars.bat file in "BIN" folder of RAD Studio
(for Delphi 10.3, its default location is is "c:\Program Files (x86)\Embarcadero\Studio\20.0\bin\rsvars.bat", but it can be different if you installed RAD Studio in a different folder).
All paths in this file must be correct, especially "BDS", "BDSINCLUDE".