DayBack won't open on my FileMaker Server
1. Make sure you have sharing turned "on" for the DayBack file. Open the file on your local machine and head to File / Sharing / Share with FileMaker Clients. Then find DayBack in the list of currently open files and set sharing to "all users". If you want to get fancy you can restrict sharing by privilege set as well.
2. If sharing is already on, it may be that your FileMaker Server is set to allow only a small number of open database files. In the FileMaker Server admin console, The Database Server > Databases tab specifies the maximum number of files that FileMaker Server can host: try increasing that.