Hi again. I'm still getting the error, but I'm not sure the upgrade is being applied correctly. Going to Community Builder: New Install CB Plugin and uploading the downloaded file joomlaplugin_cbpaidsubsbot-4.1.0+build.2016.11.16.23.56.48.1a7e1aade, I get the success message, but :-
Although the plugin management list shows build 4.1.0+build.2016.11.16.23.56.48.1a7e1aade installed and published against all CBsubs plugins, when I go to CBSubs, it still shows 4.1.0+build.2016.09.20.07.58.14.931a0995b
Jim