This type of issue is uncommon, but can occur as a result of a specific set of circumstances.
Many executables write output to log files named exename.$PID.log, where $PID is the windows process ID, e.g., CheckSystem.7632.log. At the end of the run the contents of that file are read, displayed and/or stored in the database, and the file is deleted. If there is an exception or the process fails in some way, the log file can be left behind.
Later on, it's possible that a new pass of the same executable will pick up that old file's contents when the PID gets reused (there is a finite pool of numbers).
Improvements have been made in recent releases of TPAM and it is now more diligent about file cleanup. This issue is no expected to occur frequently, although occasional issues can still occur.