Problem with reports
Default reports under the Security category in Ad Hoc reports are populated based on the Event Source Updates (ESU). If the Security reports are no longer available you may want to try to run the newest ESU on your system to see if that resolves the problem.
You could check the install_HF.log and pi_webserver.log located in E:\nic\"enVision Version"\"Site Name"\logs to try to determine what cause this problem in the first place
I've seen this behavior before and is usually caused by a corrupt XML or a problem during the installation of an ESU
I hope this helps
Do you have custom reports that are supposed to exist in the Security folder? If you do, there may be a corrupt custom report that is preventing the reports list from loading.
On the application server in a LS environment or the enVision server in an ES environment, navigate to e:\nic\4100\[servername]\etc\reports\custom\
Backup the Security folder and remove it from the "custom" directory. Restart the NIC Web Server service and try to access the Ad Hoc reports Security folder again.
If this works then a custom report is corrupt.
As earlier mention by one of my friends.. Fisrt, check the %_ENVISION%/logs/pi_webserver.log on the A-SRV/ES box. It may have the name of the offending report.xml file. If not, do a search on e:\nic\<version>\<nodename>\etc\reports\custom folders. Search for any xml file that has 0kb. If there are, delete them and restart the NIC services (Restart the NIC services on the Application Srv if this is a multi-site setup).
If there are any reports with special characters in the name this will also cause the error you see above.