On Sunday night, the server component of Backup Nexus began to experience problem. Eventually, the server crashed and we were forced to restart the server.
The bun client has a feature, whereby if you have the wrong password, it will restart itself and prompt you to re-login (since if you have the wrong password, your backup data will be corrupted). However, there is a bug in the detection: the bun client considers any login failure, whether resulting from network failure or wrong password, to result in the need to re-login. Because of the recent server problem, you may have noticed that your bun client has prompted you to login again. If you see the screen, simply login again. Once you login successfully, backup of your files will resume. In addition, any files that you have previously backed up continue to be available, so you do not need to worry about data loss.
Sorry for the inconvenience. This login bug has been fixed in the latest developmental version of bun and should be deployed when the next beta comes out.