I have been having a lot of problems with the Common App tonight and know others have as well. Here's an update that the website just posted:
"This page will be updated continuously with current system status details. Last update 11:30 pm, 10/30/17
Current Status: We are aware that many applicants and recommenders are having technical difficulties this evening. We have been working to determine the cause of the problems. In order to minimize the intermittent nature of the problems and to fix them, we have decided to take the Common App offline for two hours.
The Common App system will be offline from 11:30pm - 1:30am EDT this evening.
We know that this is a stressful time for students, recommenders, and their families. We are working hard to resolve the technical difficulties as quickly and completely as possible.
We will post our next update at 1:30am EDT."