Looks like you don't have an upgrade license or if you're just trying to run software updates, your maintenance contract with emetro have expired.

If you're trying to upgrade (not update) from any software version below 4.5, you can't do it by just getting a license and running software updates. You need to re-image the drive. You can get one from emetro or you can get the 5.0 image from them and do it locally.

I'm just trying to install software updates, not an upgrade.

I see the version I have is UCx 3.0 and I need to get it to UCx 4.0.

In the past you could update the system (not upgrade) just by running the software update from the GUI Update tab.
Sometime around the release of rls 4 that ended. Assurance Support Plans must be active and valid for UCx Updates and Repositories access. (Shouldn't be that way for GPL code)

You won't be able to get it to 4.0 either. That release is due to be retired on April 30th this year and 3.0 was retired on Oct 4 2014.

To have remote vpn access, emetro technical support, purchase applications or be able to transfer licenses, you need to have an active support agreement in place.

Your best bet if you don't have a support agreement is to buy an upgrade to release 5.0. You can buy a pre-programmed drive from them or they might just send you the iso file so you can reimage the existing drive and restore your programming.

If you want to update just open source packages, you can do that. Go to System - Updates - Repositories, uncheck the four UCx repositories at the bottom (Base/Updates/Beta/Extra RPM Repository for UCx), go to the Software Update page and run the update. To get updates from E-MetroTel's UCx repositories, you'd need to have a valid support contract with E-MetroTel.

UCx release 3.0 is pretty old. The release it is based on CentOS 5, which went EOL on March 31, 2017. It uses Asterisk 1.8, which is EOF since November 21, 2015. I'd say an upgrade to UCx 5.0 might be a good idea.