When you're inside the Admin environment and you run into a db : error pop-up, please send a full sized screenshot of your screen to Support.
From the screenshot we're look for your version number that is being used and the server that you're on, as pointed out by the arrows below.
Please include the steps that you took to get where you just got.
" Admin > Contactlists: I added a new list with filters (..). I attached the contactlist for review:"
The more information you include, the better that we can help you.
After having send the information, please delete your history and cookies and reload the page. This will most likely prevent the error message.