I have never used applicationevents=false so that is not the issue. I'm not sure what Document Management software refers to. There is something wrong generally. Shellexecute works only half the time. When it fails it gives a code 29, "SE_ERR_DDEFAIL". When I restart the system, after closing everything, still Windows asks if I want to save changes to Book1 before restarting. Just now I closed everything and checked Task Manager before restarting. It says I have six copies of Excel in memory. Manually deleting them from TM avoided the restart routine asking me if I want to save.
In my research of these problems I found references to COM. One involved ShellExecute and another involved copies of closed Excel books still showing in Task Manager. The one regarding ShellExecute recommended using CoInitializeEx, however I was not able to call that function from my VBA code. Perhaps it must be initialized explicitly for C but is supposed to be automatic for VBA?