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?
Let's do some troubleshooting to ensure the Quicken software is installed and updated properly and that your data file is in good working order. Crashes or killing Quicken may damage the file.
Download and install the most recent patch file to get your software installation up to spec.
https://www.quicken.com/support/update-and-mondo-patch-20182019-release-quicken-windows-subscription-product