This just started happening yesterday. When I open the toolbar or properties windows (I have them pinned to the sides) there's nothing in them. I thought it was a setting that had been altered, but when I closed VS and re-opened it, they were there again. But now it's happening today and they're empty even if I reload. When I open the toolbar bar it just says 'There are no usable controls in this group....... ' (that's the general group, i.e there are no controls at all).

Is this a setting? Although I can't imagine a use for a setting that gets rid of all tools and properties

Just to clarify, if I open a new project, then the toolbars are normal, so I guess it's just a setting in one project?