Can't install companion app on OSX 10.13.5

[Google User]

Hi,

I've got a licence and have been using VDH fine for years. The other day I tried downloading something and was prompted to upgrade the companion app, but I can't do it successfully. What happens is:

1. I install from https://www.downloadhelper.net/install-coapp. I've tried the pkg and dmg, both have the same issue
2. Installation appears to complete successfully
3. Click "recheck" in the app settings on my browser (firefox 60) (restarting firefox makes no difference)
   
4. VDH shows an error: "Checking companion app returned: An unexpected error occurred"

How can I debug this? Where should it be installing the app, etc.?

Thanks

[Google User]

Don't worry, finally worked this out. For anyone else with this issue, make sure to run `cat ~/Library/Application Support/Mozilla/NativeMessagingHosts/net.downloadhelper.coapp.json` and make sure the "path" points to a valid location. If not, exit firefox, delete this file, restart and reinstall the companion app. Mine was pointing to an old manual installation location.

[mig]

When using the .pkg option to install the coapp on a Mac, this problem should not happen. But installing/uninstalling through the .dmg option may leave the manifest files pointing to the wrong places. Congrats on fixing the issue on your own.

[Stephen Lee]

I had the opposite problem. When I installed from the .pkg my Mac said that the package was broken and wouldn't open. When I installed from the .dmg it worked.

[mig]

The latest version (1.2.4) of the companion app has been installed 213033 times as .pkg and 86240 times as .dmg. There has been very few complaints. Maybe the problem is to be searched for obsolete MacOs version or broken OS install.