New installer is not valid 32 bit application

The new installer ist not valid 32 bit application on windows XP
with the old installer that was no problem.

I unfortunately need the computer with windows XP. I have older software that does not work properly on higher versions of Windows.

The new installer does not support Windows XP (it does work on 32 bit, but only Vista and above).

Microsoft dropped XP support 6 years ago - time to move on! You can use a VM to run old software if there really is no other way.

When 12.20 stable version is released we'll do an Installshield build which will let you install it on XP and list it separately on our website. 12.20 will be the last version that officially supports XP.

Thank you for the information.
Then Directory Opus must remain at this version on this machine.