I have a strange problem where I cannot right click any embedded
objects to bring up the context menu e.g. in order to access the
properties and changed linked cells etc...

The book still does what it is meant to do i.e. buttons still accept
left mouse clicks and scroll bars still work etc...

I tried an earlier version of the spreadsheet and it still works fine.
If I create new sheets with embedded objects they work fine but if I
copy the object into the affected book I cannot right click. Yet I can
copy a single object to a new sheet and it works fine but not multiple
objects.

Clearly it is a setting somewhere but I don't recall making changes
anywhere either by clicking or code. The sheets and book are
unprotected.

Any Ideas?

Nick