Connection is closed in pg801 using pgadmin3

Hi all

When i cancel a large query in pgadmin that comes with pg801, it shows me:

server closed the connection unexpectedly
    This probably means the server terminated abnormally
    before or while processing the request.

This happens only with this customer in particular, not in my notebook,
running the same version, what can be wrong ?

Best Regards
Rodrigo Moreno