32-bit Windows unable to run 64-bit compiled Xojo app?

According to what I read on the Xojo info page, a 64-bit Xojo-compiled Windows app should be able to run on either 32-bit or 64-bit installations of Windows. My app is 64-bit. I have a customer who is running a 32-bit version of Windows 10 who gets this error when he tries to run the app:

“The version of this file is not compatible with the version of Window’s you’re running. Check your computer’s systems information to see whether you need an x86 (32-bit) or x64 (64-bit) version of the program, and then contact the software publisher.”

Any clues as to what’s going on here?

32 bit app can run on both.
64 bit app only on 64 bit OS.

Thanks, I simply read the Xojo info page wrong.

… I’m left wondering why Windows 10 exists in a 32-bit version anyway.

So that Windows10 can run on 32bit hardware. Yes 32bit hardware does still exist and Microsoft supports it.

I always compile my stuff 32-bit for this very reason. There are still stragglers who run older 32-bit versions of Windows. It’s fairly low now, but its still out there (On the game platform Steam for example, it’s around 1.2% of systems).

A great deal of low end windows tablets are 32 bits. And the installed base is significantly 32 bit.

I see. That makes sense, thanks.

backwards compatibility
you can still run 16 bit code from the Windows 95 days …

And if you have under 4 GB of memory, there is no real advantage to 64-bit. So running in a VM with under 4GB of memory assigned, I’ve heard the 32-bit is a reasonable choice.

That’s not entirely true. Compiling as 64-bit gives you access to the LLVM compiler on Windows and may give you a little speed boost depending on the optimization level you choose.