Error Message When Updating Accounts: CC-800

To fix this issue:

Step One: Confirm you're on the latest Quicken release

1. Select the Tools > One Step Update, or you can go to Help > Check for Updates in newer versions.
2. Click Update Now.
3. If an update is available, Quicken displays a window that describes what's in the update, as well as brief instructions for downloading the update.  

Step Two: Fix the accounts causing the error

First,

1. Select Tools > Account List 
2. If present, select the Show Hidden Accounts checkbox at the bottom of the Account List
3. Select Edit on each account with this error and Deactivate them on the Online Services tab
4. When finished, close the Account List

Second,

1. Go to File > File Operations > Validate & Repair > Validate file, to fix any issues with your Online Settings
2. Close, then re-Open Quicken

Third,

1. Select Tools > Add Account 
2. Go through the process of re-adding the deactivated accounts to Quicken, providing the login credentials and answering any security questions, until you reach the screen where Quicken displays the Accounts Discovered at the financial institution
3. Select to LINK each of the found accounts to the accounts you already have set up in Quicken.