Trouble downloading updates and plugins

JMonkeyPlatform can’t check for updates or download plugins. I keep getting error messages similar to this:

Unable to connect to the Base Platform Alpha because of Server returned HTTP response code: 403 for URL:

That one was from the “Reload Catalog” button. I can download the file if I paste the link into my web browser, so I can connect to the site, but JMonkeyPlatform can’t anymore. It has worked in the past and I’m pretty sure I haven’t changed any settings.

I don’t think it’s a firewall issue since it worked before. I’m using a 2010 MacBook Pro.

Any suggestions?

Beta is out, alpha doesn’t update anymore.

Ah-ha. That would do it. Thanks!