Excel 2013 icon with a difference

[dapaulio]

Does anyone know what this symbol means on the excel icon.

 

I suspect it is causing me a problem whilst attempting a mailmerge function. the symbol seems to disappear when I open the document but returns when I close it.

 

[Rob_D]

Where are the files saved? I know cloud mapped folders (one and google drive) user similar symbols.

[dapaulio]

On a Network share. I had considered that. The user has an application called Egress installed which has a similar coloured symbol but not the same. Coincidence??? If I disable egress the icon remains.