Problemas para subir posrtgres

Señores

Al instalar un obdc en la maquina que tenia postgreSQL se daño el postgres,
creo, este es el mensaje que me da al hacer /etc/init.d/postgres start

Starting PostgreSQL database server: postmaster(FAILED)
ERROR: cat: /var/lib/postgres/data/postmaster.pid: Permission denied
pg_ctl: Another postmaster may be running. Trying to start postmaster
anyway.
sed: can't read /var/lib/postgres/data/postmaster.pid: Permission denied
ERROR: PostgreSQL postmaster did not start because of an unknown reason.
PostgreSQL's init script (/etc/init.d/postgresql) attempted
to start the postmaster, however, this failed because of an unknown
reason.

This should not happen and is a serious problem. Please examine the
situation (please take a look at the log files). If you know the
reason why it failed and, then please file a bug report to Debian
(unless the reason is something obvious like a full disk).

Debian PostgreSQL
**************************************

eso es, los permisos de postmaster son -rwxrwxrwx 1 postgres postgres 47
Oct 24 11:44 postmaster.pid

Todo esto paso cuando intente istalar un ODBC para conectarme a una BD SQL
SERVER

por que me dice "pg_ctl: Another postmaster may be running. Trying to
start postmaster anyway."

¿Si instalo otra vez pierdo todos los archivos?