When Scanner Appliances (physical appliances or virtual machines) are not updating or do not execute scans as instructed, a common cause is their inability to reach Qualys' datacenter when traffic is going through a web proxy.
An easy way to test whether this is the case is to connect a laptop which has the same configuration as the Appliance in lieu of the Appliance and to try to access the Quays datacenter via a common browser.
Try to manually navigate to the following pages if you are on Qualys' 2nd EU datacenter (see below on how to determine which URLs apply to you):
What You Should be Seeing
Finding the URLs for Your Account
Once logged in to your Qualys account, go to "Help", "About", and see the URLs listed for your account in the "Secure Operations Center" of the "General Information" tab. Compare the expected results with the screenshots shown above.