I got this error at configuration time: You do not have write access to create install directory given with --prefix=/usr/local/petsc/dev/linux-gnu perhaps use --with-sudo=sudo also Then I've added, the sudo stuff and worked. However, after the configuation, the dir was not created. So the question is: in which scenario PETSc does need access to the install dir at configuration time? -- Lisandro Dalc�n --------------- Centro Internacional de M�todos Computacionales en Ingenier�a (CIMEC) Instituto de Desarrollo Tecnol�gico para la Industria Qu�mica (INTEC) Consejo Nacional de Investigaciones Cient�ficas y T�cnicas (CONICET) PTLC - G�emes 3450, (3000) Santa Fe, Argentina Tel/Fax: +54-(0)342-451.1594