The policy store is not available; please see the log files for more details

After installing OAM 11gR2, you are getting error while loging into oamconsole.

You did the same mistake which I did of not reading the product documentation before starting with the installation.(http://docs.oracle.com/cd/E27559_01/install.1112/e27301/install.htm#INOAM98374)

There is an additional step in OAM 11gR2 (11.1.2.0) which says before starting up the servers, you need to configure the Security Store.

Follow the below steps to fix this error:

Solution
-----------
1) Delete the Domain
2) Remove the schema from RCU
3) Create the schema again.
4) Create the domain by running config.sh
5) Now the missed step, run the configSecurityStore as below:

$MIDDLWARE_HOME/oracle_common/common/bin/wlst.sh
$ORACLE_HOME/common/tools/configureSecurityStore.py -d $DOMAIN_HOME -c IAM -p <opss_schema_password> -m create

6) Start up the servers.

This should fix the issue.