Hi, Lymm!
The first message seems to be a security issue regarding macros and its enabling.
Try with the info in this article:
http://office.microsoft.com/en-us/change-macro-security-settings-in-excel-HP010342232.aspx
Set Disable All Macros With Notification, Trust Access To The VBA Project Object Model, both to on. And then try again.
BTW, do you use TeamViewer or LogMeIn? Those are applications for remote support. The first one is very simple, you install it, you run it, it gives a number for your PC's session, you send (mail, not here) the number, and I can enter and perform these and further operations accessing to your keyboard and mouse. You'll be seeing what I do, and you can terminate the session at any time. When finished, you might opt for uninstall the application, if you wish.
Regards!