The .NET Framework is a software framework developed by Microsoft that runs primarily on Microsoft Windows.
In order for TxtReaderXpress operating correctly. User have to install .NET Framework 4.6 runtime, .NET Framework 4.6 runtime is per-installed on Windows 10. For other Windows user, please download and install the .NET Framework 4.6 runtime.
For the normal operation when open OpenOffice document, indeed to install .NET Framework 3.5 runtime, because of the 3rd party OpenOffice class assembly.
Download .NET Framework runtime