If you haven't rebooted Windows since you installed the latest software update, please do so now and then try Quicken again.
Still not working?
Please perform the steps in this document:Troubleshooting 101 - Fixing Installation and Data File Problems
Also please verify these settings:
Go into Control Panel / Internet Options or Start Internet Explorer. Click on Tools / Internet options.
Click the Advanced tab. Ensure that all "Use TLS 1.0, 1.1, 1.2" have checkmarks. Uncheck all "Use SSL x.x" Click the Contents tab and click the "Clear SSL state" button. Click Apply, then OK. Close IE. Close and restart Quicken and see what happens.