VCL Compile and Install Errors

Apollo missing from Library path

The following is a common fix to resolve issues related to compiling and installing Apollo into Delphi/RAD Studio. One of the most common error messages related to this is:

[dcc32 Fatal Error] apollo9D103.dpk(51): F2063 Could not compile used unit 'APCOMMON'

This issue can usually be resolved by adding the Apollo path to the Delphi/C++Builder Library path. Depending on your version of Delphi, the following steps may vary slightly. You need to edit the Library Path and the folder where your instance of Apollo is installed on your computer to this path.

  1. Run Delphi 11
  2. from Tools -> Options -> Environment Options -> Delphi Options -> Library -> edit Library Path ...
  3. Add "C:\Apollo\[majorversion.minorversion]\x64\VCL\D10" to your Library Path (or wherever you installed Apollo)
  4. Save and try re-installing


  • If you have any previous versions of Apollo installed, remove any references to the old Apollo folders from the Library path.
  • To install the 32-bit version of Apollo, use the \x86 folder instead of the x64.

  • Note that the Trial does not include the .PAS source files, it only includes the pre-compiled .DCU files