thanks for the reply.
I did not realize Dynare switched all warnings on .

It seems though that the problem lies with MATLAB 2008.
For those interestedâ€¦
the matrices I posted are the matrices of a two-country model with financial frictions and sticky prices. It solves fine in Dynare and with other solvers. The function ordqz of Matlab works fine with Matlab 2007 but gives the warning with Matlab 2008 (both Windows and Linux) .