Hi
Now with Android 8.0 Oreo it is no longer possible to install any application of the site.
There is more possibility with Android 8.0 Oreo to put "unknown sources"
What to do ?

[robstillholdin]

You are mistaken my friend. Still fully capable of installing from unknown sources

Since switching to Android 8.0 Oreo when I want to install an application from the site I have this error message "There was a problem parsing the package" and I could not install the application.
And that with any application of the site
What does that mean ?

[kirpeace]

I know you will get that message if you have that app already downloaded, being from here, there, play store or wherever. Try uninstall and reinstall from here..?? If that`s the case.