i have been trying for so long.
So far the only thing worth mentioning is that windows system restore works !!!
Unfortunately on my other pc system restore was disable.
for that pc i have tried everything. uninstall, repair, copy cinerender folder from my working pc ,no grass enable dejrolon - thanks for trying to help- nothing . when trying to preview a render or choose to render the message " CineRender by MAXON add-on has unexpectedly closed." appears and suggests to restart archicad
p.s i also noticed that cinerender.exe doesnt run in taskmanager> processes even before i try to make a render, while on my restored working pc its there the moment i launch archicad 20.
help
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update :
ok i think i found it after a long long struggle.
i think after reinstalling repairing Visual C++ Redistributable Packages for Visual Studio 2013
which i downloaded directly from microsoft the problem was solved. now cinerender loads in the background and preview and rendering with maxon engine work fine .