We have a System Center Essentials (SCE) server to filter updates to our laptops. We've configured it to download the update, and then the laptops get the update from this server; this of course reduces our internet bandwidth and the time it takes for employees to receive the updates, which reduces the complaints we get about how long updates take.

However we currently have a total of 2,255 updates stored on the server. SCE gives a breakdown:

Updates with installation errors: 29
Updates needed by computers: 280
Updates installed/up-to-date: 0
Updates with no status: 1946

Our little server has 68gb of hard disk space, and the updates are currently taking 32gb and counting.

Some of the updates date back to 2003, but we can't figure out a way to delete them to free up space on the server. Right-clicking an update and clicking Uninstall threatens to remove the update from all computers, which is not what we want. Some of the updates even inform us upon viewing:

This update has been replaced by a newer update. Before declining this update, it is recommended that you approve the new update first and verify that this update is no longer needed by any computers.

How do you prevent your SCE server from filling its hard drive space? Is there a way to configure the server to only keep updates that are still needed?

Furthermore, why (in the above breakdown of updates) are there so many updates with "no status" and 0 updates that are "installed/up-to-date"?