If you haven't rebooted Windows since you installed the latest software update, please do so now and then try Quicken again.
Hello @Mark Repinski Thank you for reaching out to the Community regarding your issue, though I am sorry to hear that you are experiencing this.
If you do experience issues after you have tried the backup we would recommend contacting Quicken Support directly for the best assistance. We have a tool available that will let us remove the password so you can reset it as long as you're able to answer a couple of questions about the file. I will leave our hours down below so you can find a time that works best for you. Additionally for more information on the problem I'll leave an additional link.
https://www.quicken.com/support/what-if-quicken-not-accepting-data-file-password
Click here to review Quicken Support's hours of operation. Thanks, Quicken Francisco