Problem with ActiveSheet VBA code when it is the open but not in focus

[ThiaJay]

My worksheet contains VBA to control the order of tabbing. It activates when sheet is activesheet and disables when it's not. The problem I encountered today, is that I switched to another application, tried to tab and it was trying to open up the workbook containing the tab controlled worksheet.

Is there anything I can do about this?

https://docs.google.com/spreadsheets...f=true&sd=true

Thanks for your help.

[TMS]

Please post your code and, ideally, upload the workbook, not a link.

[ThiaJay]

ThisWorkbook:

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Clipboard Worksheet

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Clipboard Module

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[ThiaJay]

Attached as requested.