Fix Personal.xlsb is Locked for Editing
Using Excel Version 2006 13001 20266:
PERSONAL.XLSB is Locked For Editing occurs while attempting to open an Excel file.
From Excel, navigate to File->Open->Browse
Make sure Preview Pane is Enabled
Click on any Excel File.
You may receive a popup error (Hidden behind the currently open Excel window) stating PERSONAL.XLSB is loced for editing.
This is because Excel requires a second instance to preview the file. When instantiating Excel the second time, the PERSONAL.XLSB file attempts to open. Because it is already open, the second attempt to open the file results in "PERSIONAL.XLSB is locked for editing.
The workaround is to disable the Preview window in the Open Dialog.
Microsoft should fix this!