Yes, sorry about posting the error, I accidentally ran Paraview whilst in virtual environment of VTK. But the performance is quite terrible. With vti file of 200 Mb, client is quite lagging when requesting 2D images from server. Do you have any hint to boost the performance. Here is the file that I am using: 209.64 MB file on MEGA . Server is running fine without error log. The issue is only performance.