Re: [Problem] - Error: cannot open pg_class_oid_index: Permission denied

"Selvakaruppiah s-TLS,Chennai" <Selvakaruppiahs(at)hcl(dot)in> writes:
> Actually my application is using the postgres 7.2.4 as backend.

[ blink... ] Please tell us that is a typo. 7.2.4 is more than five
years old, and the entire 7.2 branch was abandoned as unfixably buggy
and insecure more than three years ago. If you're using a software
distribution that presents 7.2.4 as a current version, then you have
equally bad problems for every other part of that distribution.

> Mac 1: At 6:51:15 - ERROR: cannot open pg_class_oid_index: Permission denied

The only cause I've heard of for sudden occurrences of "permission
denied" errors on databases that had been working is interference
of broken Windows antivirus software. If you're running 7.2 atop
Cygwin atop Windows (which is the only way 7.2 could have run on
Windows) then you really are working with a house of cards --- get
yourself to a native PG install using recent 8.2.x or 8.3.x. Your
AV software will still be just as broken though, so you likely
also need to update or remove it. (Dare I suggest installing a
real operating system instead of M$?)

regards, tom lane