# KSP_DIVERGED_PC_FAILED
It was not possible to build or use the requested preconditioner. This is usually due to a zero pivot in a factorization. It can also result from a failure in a subpreconditioner inside a nested preconditioner such as `PCFIELDSPLIT`. 


## Notes
Run with -ksp_error_if_not_converged to stop the program when the error is detected and print an error message with details.


## See Also
 `KSPSolve()`, `KSPGetConvergedReason()`, `KSPConvergedReason`, `KSPSetTolerances()`


## Level
beginner

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/include/petscksp.h.html#KSP_DIVERGED_PC_FAILED">include/petscksp.h</A>


---
[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/include/petscksp.h)


[Index of all KSP routines](index.md)  
[Table of Contents for all manual pages](/docs/manualpages/index.md)  
[Index of all manual pages](/docs/manualpages/singleindex.md)  
