miniSIPServer old versions save CDR records into some binary files in “AppData/cdr” directory. If you want to check history records, you have to start miniCDR tool to open them. If you want to do more research, you will have to use miniCDR to convert them into CSV format files.
Now miniSIPServer new version ( I mean V39 or newer) will save CDR records into CSV files directly. Of course, all these .csv files are still stored in “AppData/cdr” directory. Since .csv files are text format, you can use any text tools, such as notepad in Windows and Gedit in Linux, to open them. If you have Excel, you can use it to open and analyze these CDR files directly too.
And miniCDR is upgraded at the same time to be able to process previous .cdr files and new .csv files.