# ParaView MPI Autostart issues on Mac OS
**URL:** https://discourse.paraview.org/t/paraview-mpi-autostart-issues-on-mac-os/4336
**Category:** ParaView Support
**Created:** [May 15, 2020, 2:55am UTC](https://discourse.paraview.org/t/paraview-mpi-autostart-issues-on-mac-os/4336 "2020-05-15T02:55:10Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@bluecore](https://discourse.paraview.org/u/bluecore)
#### Post date: [May 15, 2020, 2:55am UTC](https://discourse.paraview.org/t/paraview-mpi-autostart-issues-on-mac-os/4336/1 "2020-05-15T02:55:10Z")
I am having quite peculiar issues with running paraview in parallel on Mac OS. I’ve downloaded the 5.8.0 version of paraview and launched without any difficulties. I have an 8-core MBPro and so I tried to launch the MPI autostart, which spawned 8 separate processes of pvserver and I was able to do my work without any problems.
However, while closing paraview, the spawned pvserver applications would be still running, and so I had to forcefully close them. Since then, if I try to autostart paraview with MPI support, this is the message I receive:
_Generic Warning: In /Users/kitware/dashboards/buildbot-slave/a64f5607/build/superbuild/paraview/src/Remoting/ServerManager/vtkSMSession.cxx, line 288_
_Failed to automatically launch ‘pvserver’ for multi-core support. Defaulting to local session._
What is even more interesting, is that I tried ParaView 5.6.0, which worked in MPI until I had to close the application. For second run, it would never start again in MPI.
I have reverted to use pvserver and call with mpiexec provided in /Applications/ParaView/Contents/bin, however once I run ./mpiexec -n 8 ./pvserver --mpi (or without suffix --mpi), the terminal just hangs and doesn’t do anything.
Is anyone experiencing such issues? What could be the source of the problem?
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### Author:  [@cory.quammen](https://discourse.paraview.org/u/cory.quammen)
#### Post date: [May 15, 2020, 3:05am UTC](https://discourse.paraview.org/t/paraview-mpi-autostart-issues-on-mac-os/4336/2 "2020-05-15T03:05:50Z")
Welcome to the ParaView Discourse forum, Matus. What version of macOS are you running?
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### Author:  [@bluecore](https://discourse.paraview.org/u/bluecore)
#### Post date: [May 15, 2020, 5:18am UTC](https://discourse.paraview.org/t/paraview-mpi-autostart-issues-on-mac-os/4336/3 "2020-05-15T05:18:34Z")
Thank you Cory. macOS Catalina (10.15.4).
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### Author:  [@bluecore](https://discourse.paraview.org/u/bluecore)
#### Post date: [June 5, 2020, 10:10am UTC](https://discourse.paraview.org/t/paraview-mpi-autostart-issues-on-mac-os/4336/4 "2020-06-05T10:10:05Z")
Any solution for this?
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### Author:  [@cory.quammen](https://discourse.paraview.org/u/cory.quammen)
#### Post date: [June 5, 2020, 4:42pm UTC](https://discourse.paraview.org/t/paraview-mpi-autostart-issues-on-mac-os/4336/5 "2020-06-05T16:42:45Z")
My guess is that some security mechanism in macOS Catalina is preventing the auto starting of pvserver. I don’t have a Catalina machine on which to test this out though.
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### Author:  [@wascott](https://discourse.paraview.org/u/wascott)
#### Post date: [June 5, 2020, 5:00pm UTC](https://discourse.paraview.org/t/paraview-mpi-autostart-issues-on-mac-os/4336/6 "2020-06-05T17:00:29Z")
Works correctly for me. I am on Mojave 10.14.6. Tested with ParaView 5.8.0, used the GUI Preferences “Enable Auto MPI”.