You (root) are not allowed to access to (crontab) because of pam configuration.

Error Massage :

# crontab -e
    Permission denied
    You (root) are not allowed to access to (crontab) because of pam configuration.

Solution :

open with vi /etc/pam.d/crond
#
# The PAM configuration file for the cron daemon
#
#
# No PAM authentication called, auth modules not needed
account    required   pam_access.so
to
#account    required   pam_access.so

account    include    password-auth
session    required   pam_loginuid.so
session    include    password-auth
auth       include    password-auth

Problem would be resolved.
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