[Puterde]

Hello everyone,
I am newbie of openfoam and installed openfoam-dev in ubuntu 18.04 yesterday, everything well on well when I tried the example of cavity with the tutorial until I want to use paraFoam to verify the mesh. At first, there was nothing but blank window when I opened the paraFoam, and then it showed:
X Error: BadAccess (attempt to access private resource denied) 10
Extension: 130 (MIT-SHM)
Minor opcode: 1 (X_ShmAttach)
Resource id: 0x12bX Error: BadShmSeg (invalid shared segment parameter) 128
Extension: 130 (MIT-SHM)
Minor opcode: 5 (X_ShmCreatePixmap)
Resource id: 0x22000d5X Error: BadDrawable (invalid Pixmap or Window parameter) 9
Major opcode: 62 (X_CopyArea)
Resource id: 0x22000d6X Error: BadAccess (attempt to access private resource denied) 10
........ and so on
Does anyone else meet this situation before and tell me how I can deal with it? pls.
Thank you very much