I found this thread on Google that indicates a bug in the released build of MFC70.DLL. It turns out that the DLL doesn’t delay load OLEACC.DLL (Active Accessibility) and so loads it even if you’re not using any accessibility features. This causes problems on Win95 (where it isn’t normally present) and on systems where it wasn’t chosen to be installed. Worse, if someone choses to uninstall Active Accessibility, all the MFC7 apps will stop working.
This post in the thread describes how to make a dummy OLEACC DLL that you can drop into your app folder.
One thing that I hadn’t noticed before is that Microsoft are recommending that you put MFC70.DLL and MSVCR70.DLL in your application folder since they are no longer classed as system files and shouldn’t really be in SYSTEM32. Visual Studio.NET puts them there for convenience so that you don’t have to keep copying them for each build type of each project you develop.