Can't Install Any Extensions (since yesterday?)

Hi,

Whenever I try an open the “Install KNIME extensions” menu, I get the following message:

and I can’t install anything.

To try fix this, I re-installed KNIME, but now all my previously installed extensions have been removed and I’m still getting the exact same error message. Looking through the forums, some people suggests removing the “s” from “https” in the software site menu, but this still does now allow KNIME to download anything.

I believe my installation was working fine yesterday. Does anyone know how to fix this?

Thanks for the help