Automated Logic’s WebCTRL is a premier building automation system, offering an intuitive user interface and powerful control features.

Besides the obvious wrong credentials, you could be experiencing a database issue.

If you lose connection to the database server (MySQL, MSSQL, Postgre etc) that WebCTRL is using that will result in the same thing because it can't check your login credentials. Shut the WebCTRL system service down and see if you can open the system in SiteBuilder.

Also the login name is a drop down list in SiteBuilder and that removes half of the things you can get wrong with the username/password question on the web page.
- Scott Jalbert