How to Fix : Microsoft Office Has Identified a Potential Security Concern

Microsoft Office has identified a potential security concern.
File path: c:\My Documents\EA.xlsm
Data connections have been blocked. If you choose to enable data connections, your computer may no longer be secure. Do not enable the content unless you trust the source of the file. [Enable] / [Disable]


FIX / SOLUTION

I just spotted a button on the 'view' tab which said 'unhide'. I clicked it and it offered to unhide the workbook.