Strictly speaking this isn't a problem unique to Oracle Portal, and certainly not unique to just Oracle software. But it's starting to drive me crazy--these obtuse and undecipherable error messages that the software spits out.
Case in point is the Reports servlet that comes with our Oracle Portal install. There were a number of reports failing today with the following error message:
Finished successfully but output is voided
Turns out after a quick search thru Metalink (http://metalink.oracle.com/) that the cause is simply that a report has generated output larger than the cache size allowed for the server. You can tweak the cache size by editing the cacheSize property in the reports config file (usually found in the $ORACLE_HOME/reports/conf directory).
What annoys me is that obtuse error message. Why can't it just say Report larger than available cache or something more human-readable?