Having trouble saving PERSONAL workbook on new laptop

Tried putting it in the XLSTART folder. I get this error message when I try to save it afterwards:


First popup:

Microsoft Excel cannot access the file 'C:\Program Files (x86)\Microsoft Office\Office14\XLSTART\78AF0500'. There are several possible reasons:

The file name or path does not exist
The file is being used by another program
The workbook you are trying to save has the same name as a currently open workbook.

Second popup

You cannot save the Personal Macro Workbook in the startup folder. Save it elsewhere now and move it to the startup folder later.



...I tried saving it elsewhere and moving it in later, but I get the same message??




I also tried using it as an add-in.. but when I press Alt+F8... none of my macros show up in the window? How do I make them show up there?

Thanks!