I have one standard gmail account already set up in Thunderbird, and I tried to add my university and my work accounts (both offered through gmail), but was unable to do so. In the process, I received a couple of error messages. The first one said that the "incoming server already exists" (I imagine because the same server name (imap.gmail.com), port (993), and security protocol (SSL/TLS) are configured for my first gmail account). The other error I received was when I was able to pass that first message (by changing the configuration for my first gmail account) and the login screen actually appeared. I was able to enter my email address, but not able to continue, as the gmail interface asked for my email address again (and again and again), so I was never able to enter my password. This problem is captured in the two images (the first one is when I enter my email; the second is after immediately after I click "Next.") Any help would be much appreciated!