There is a known issue where the standalone reports server can fail to start in OPMN. If this is the case, check in $ORACLE_INSTANCE/diagnostics/logs/ReportsServerComponent/$NAME_OF_REPORTS_SERVER/rwserver_diagnostic.log for the root cause of the error. If you see the following error appear and you are working with the DISPLAY environment variable if set in your environment:
[REP-56105] [oracle.reports.server] [tid: 11]
[ecid: ###################] EngineManager:manage
Engine rwEng-0 died with error: {1}.REP-0004: User preference file
cannot be opened.[[
REP-0004: User preference file cannot be opened.
You may need to have the REPORTS_DEFAULT_DISPLAY variable set to YES inside of reports.sh. Normally it is set to YES, but in case it is set to NO, you may follow these steps to fix the problem:
1. Go to $ORACLE_INSTANCE/config/reports/bin
2. Make a backup of reports.sh
3. Open up reports.sh in a text editor.
4. Scroll down to near the end of the file until you see the variable REPORTS_DEFAULT_DISPLAY. Change the value from NO to YES.
5. Save and close the file6. Restart WLS_REPORTS
After applying the steps above, you should be able to successfully start up the standalone reports server.
NOTE: This will also work if you experience the same issue with the in-process reports server.
Source: Oracle Support note 1421439.1
