Excel VBA Workbooks, Reference, Open, Add, Name, Save, Activate, Copy, Close Workbook

I have spent far too much time trying to find a simple solution to the problem of checking to see if an Excel workbook is open. After following many dead ends and misleading posts I eventually hit on this website here:-

Excel VBA Workbooks - Reference, Open, Add, Name, Save, Activate, Copy & Close Workbooks; SendMail Method

I found the code I needed, it was succinct, self explanatory and of the type/format I understand. I can't vouch for the rest of the code on this site, however going by the code I have used I should imagine it's very good!!!

Excel VBA Workbooks, Reference, Open, Add, Name, Save, Activate, Copy, Close Workbook