Another possibility is that there is there is corruption in the SRM database. The first thing to check is the $SPECROOT\tomcat\logs\stdout.log (Windows) or catalina.out (UNIX)
Look for messages that the reporting database is corrupted or that a specific table is corrupted or damaged. Here is an example: java.sql.SQLException: Can't open file: 'event.MYI' (errno: 145). If you find corruption, then try to fix it.
1. Log into the SRM system as the user that owns the Spectrum installation
2. If on Windows, start a bash shell by running "bash -login"
3. cd to the $SPECROOT/mysql/bin directory and enter the following command:
./mysqlcheck -uroot -proot --repair --force reporting
4. Let the above command run till completion. Depending on the size of the reporting database, this could take time.