Starting Project for the first time will upgrade your old Global.mpt file
If you have made any changes to the global settings from your last version of Project, those changes have not been incorporated into the global settings for projects opened with Microsoft Project. The global file contains information you can use for different projects, such as views, calendars, reports, tables, filters, toolbars, menus, macros, and option settings.
Using the Planning Wizard, you can:
Upgrade automatically.
Project will move all the settings you customized in your old global file into the new version of the file automatically.
Upgrade manually.
Project will give you an opportunity to choose which settings you want to move by using the Organizer.
Not perform an upgrade at this time.
Project will not incorporate any changes into the Project global file from your older version of the file.
If you don't want the Planning Wizard to display this information again, select the Don't tell me about this again check box.