Actually, i faced this problem again, because switching off the security option is not acceptable workaround, and i need to find a better solution.
I distribute a .pdf file on DVD and provide the ability to open it by clicking a button in custom application built using old-scool Multimedia Builder.
By some reason AR XI starts in background in this case.
I've created "one-button C# application" which opens .pdf. It works fine irrespective of it's location (local or network) and location of specified .pdf.
But once i run that OpenPDF.exe from DVD-program (it could be started from local copy) - it becomes incapable to run AR XI correctly.
I even can't imaging where to start digging.
Then i check both OpenPDF.exe using Russinovich's Process Explorer, i notice, that DVDSetup.exe\OpenPDF.exe doesn't provide information about it: [Error opening process] in it's Path, Command line etc; both processes are runnig under same windows user.
The behavior remains with switched off / on UAC. Running DVDSetup.exe under Administration account doesn't change the result. Yeah, it worked fine on Win 7 and with AR X.