procmail Suspicious rcfile

procmail: Suspicious rcfile "/home/user/.procmailrc"
procmail: Couldn't read "/home/user/.procmailrc"

If your rcfile's permission is not correct, you'll see something error like above.
/home/user/.procmailrc must have permission 644
ref. man procmail
Suspicious rcfile "x"
The owner of the rcfile was not the recipient or
root, the file was world writable, or the direc-
tory that contained it was world writable, or
this was the default rcfile ($HOME/.procmailrc)
and either it was group writable or the directo-
ry that contained it was group writable (the rc-
file was not used).