The master file is the file from which all subfiles are derived, and will be the file in which the data for the entire project will ultimately reside. You must have a master file before you can create any other files.
Creating a Master File
There are three ways in which you can create a master file:
1. New File
Open a new file using the New Datafile menu command. This will give you a new master file without any data in it.
2. Recycle an Existing File
Convert any existing master file or subfile into a new master file using the Tools Menu/Subfiles/New Master File menu command. This will give you a new master file without any cost item data or subfile records in it, but with all the general data and report configurations from the old file. You can optionally retain the cost breakdown structure as well.
3. Mandrel 1 Files
Any Mandrel 1 file can be used as a master file. Mandrel 1 is the single-user, desktop version of Mandrel without work sharing facilities.