Hi martalaura,
In addition to my first reply, ActiveMovie is the default media player of Windows 10. You can change the setting on your computer so the files will playback on PlayMemories Home. Go to your Control Panel and click on Default Programs. Select Set your default programs, highlight PMH and left click on Set this program as default.
As for uninstalling and reinstalling the PlayMemories Home software, please click here to uninstall and this one to reinstall it.
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