Installing .OCX files is a relatively simple process. On a 64-bit Windows system, you can use both 32-bit and 64-bit OCX files. Place 32-bit OCXs in the '/Windows/SysWOW64' directory and 64-bit OCXs in the '/Windows/System32' directory.
Installing .ocx files directly into the software application folder where the corresponding .exe file is located offers several advantages and is generally a safer approach than immediately placing them in the Windows system folders.
Receiving a .ocx error on startup typically means a startup program is trying to access a missing .ocx or remnants of old software. Ensure all programs are correctly installed and that there are no leftover traces of old software.