Windows 7 and 8 designed app won't run on fresh Windows 10, but will on Windows 10 upgrade from 8

So, I have been trying to get a Windows 7 and 8 designed app to work in Windows 10, but it seemed like there was no way. Up until today, that was, when I upgraded a PC with Windows 8 to Windows 10: that app was installed on the machine when running Windows 8 and I expected it to crash after the update – it didn't, rather it worked flawlessly. That app is a Windows Vista Sidebar port for Windows 7 and 8 x64 only, with no bloat. It was the most similar program to the original I could find on the Internet at some point, and still seems to be.

Why does this app work after an update and how can I get it working on a fresh Windows 10 installation, with no OS upgrades in the process?

Here is the installer, if needed:
Windows Sidebar Installer: "setup-x64.exe"

ERROR:

EDIT: The error seems to be caused by oleaut32.dll. I tried replacing mine in System32 with the one in the PC where I did the upgrade, but the program is still crashing.

Event Viewer report:

Log Name:

Application Source:

Application Error Date: 07.04.2019 22:51:22

Event ID: 1000

Task Category: (100)

Level: Error

Keywords: Classic

User: N/A

Computer: Alexa-PC

Description: Nume aplicație cu defecte: sidebar.exe,

versiune: 6.0.6001.16510, marcaj temporal: 0x4625ae7c

Nume modul cu defecte: OLEAUT32.dll, versiune: 10.0.14393.0, marcaj temporal: 0x57899944

Cod excepție: 0xc0000005

Deplasare defect: 0x0000000000002255

ID proces defect: 0x8f0

Oră de început aplicație cu defecte: 0x01d4ed7b46a74e6c

Cale aplicație cu defecte: C:\Program Files\Windows Sidebar\sidebar.exe

Cale modul cu defecte:

C:\WINDOWS\System32\OLEAUT32.dll

ID raport: 3b407c5a-f6eb-4909-82c8-9ed0e86f9861

Event Xml:

xmlns="http://schemas.microsoft.com/win/2004/08/events/event">

  

   1000

   2

   100

   0x80000000000000

  

   1161

   Application

   Alexa-PC

  

   sidebar.exe

   6.0.6001.16510

   4625ae7c

   OLEAUT32.dll

   10.0.14393.0

   57899944

   c0000005

   0000000000002255

   8f0

   01d4ed7b46a74e6c

   C:\Program Files\Windows Sidebar\sidebar.exe

   C:\WINDOWS\System32\OLEAUT32.dll

   3b407c5a-f6eb-4909-82c8-9ed0e86f9861

  

  

  

  

Answer

The solution seems to be as follows: the Windows Sidebar in Windows Vista has code in the Registry. The executable needs to be registered using the command sidebar.exe /regserver after adding the registry keys for the Windows Sidebar. After that, all the gadgets will work.