What was the prompted error message? Was it about file corruption or what?
If corruption would be the issue, you would need a third-party recovery tool that can recover your data from corrupted Exchange BKF file. I can recommend you SysInfoTools Exchange BKF Recovery solution here. It will recover all three files, i.e. STM, EDB and Log, from corrupted BKF file of Exchange Server. Read more about this tool on SysInfoTools' website