Search notes:

Personal.xlsb

Personal.xlsb is a special Excel Workbook whose macros are available to all opened Excel workbooks.
Excel itself refers to Personal.xlsb as the Personal macro workbook when asked if modification to it should be changed.

Default location

The default location (directory) for Personal.xlsb seems to be %appdata%\Microsoft\Excel\XLSTART. This directory can be determined in VBA with application.startupPath.

Hide automatically opened Personal.xlsb

When such a Personal.xlsb has been created, it will automatically be opened (and visible) whenever Excel is started.
Personal.xlsb can be made invisible when Excel is started by using the View -> Window -> Hide menu.
In order to make changes to Personal.xlsb, it should be made visible again.
With VBA, Personal.xlsb can be hidden like so: 
workbooks("Personal.xlsb").windows(1).visible = false

Disabled Personal.xlsb

Apparently, a Personal.xlsb workbook can become disabled. If so, it can be enabled again with

See also

Excel helpers
Excel15.xlb
Create a Personal.xlsb from the command line

Links

James E. Martins wheatblog entry Where is the Excel Personal Macro Workbook Located? was quite helpful.

Index

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