I get the following error when trying to compile a Web core project that uses XData.
Also XData, Web Core (and many other components) where installed via smart setup.
Error:
Pas2JS Compiler version 3.3.1 [2025/08/05] for Win32 i386 / TMS WEB Core version v3.0.2.0
[Error] Login.pas(14): can't find unit "XData.Web.Client"
You need to add the XData source folder to the TMS WEB Core library path. See IDE under Tools, Options, TMS WEB, Library path
I added the XData source folder and also BCL source, now i get the following error:
[Error] XData.Web.Response.pas(9): identifier not found "Variant"
"Variant" is defined in System.Variant, do I really have to add all of the (Delphi) library paths also to tms web core and how do I do that?
OK, found out, that I have to add
If I add tms.biz.xdata\source\core\* it does not work 
(very confusing...)
Read elsewhere here in the forum, that this should work "out of the box" if I install webcore and XData va TMS setup. Why is this not working on my side or how can I fix that issue?
Try to uninstall both, clean up what has been manually tweaked, and install it again.
Do I have to respect a "defined order" in reinstalling the two packages?
In theory, no, but since you ran into issues, try to install Web Core first, launch Delphi, add proper licensing, then install XData.
Had no luck. I uninstalled WebCore and XData via TMS Setup and then reinstalled WbCore first, checked licensing and deleted all "manually added" Library paths. After that installed XData via TMS Setup.
While compiling my WebCore Project I still get the error:
Pas2JS Compiler version 3.3.1 [2025/08/05] for Win32 i386 / TMS WEB Core version v3.0.2.0
[Error] IndexedDBHandler.pas(11): can't find unit "XData.Web.Client"
Error during compilation
Do you have the logs.zip file of that process? If you have used Smart Setup after that I'd ask you to repeat the process again and send us the logs so they contain exactly the results of the last Web Core/XData installs.