10.4.0.0 fails to build 64 bit for CPPB 10.3.3

Hi, I have C++ Builder 10.2, 10.3.3 and 10.4.1 installed, and have just installed 10.4.0.0 of the VCL UI pack. For 10.3.3 the 64 bit build fails and leaves the Win64\Release folder empty. The other versions are fine. In the log I see this message:

TMSVCLUIPackPkgDXE12.dpk(179): error E2202: Required package 'vcl' not found [C:\Users\Robin\Documents\tmssoftware\TMS VCL UI Pack\TMSVCLUIPackPkgDXE12.dproj]

Thanks.

This is an IDE config issue.
Find file VCL.DCP on your system and make sure that the folder where this file is found is added to your library path.

Do you mean in the IDE in Tools / Options / Language / C++ / Paths and Directories / Windows 64 bit / Library Path ?

The first entry is $(BDSLIB)\win64\release which looks correct and this folder contains vcl.dcp.

The installer uses MSBUILD to compile. I suggest to test with MSBUILD from the command-line to see if it picks up the correct library path to find the vcl package.