The QTP license server can be configured to store usage logs. The LSERVOPTS environment variable is used on the license server host system to affect license server performance or configuration.
Set or create a system variable called LSERVOPTS. The value should contain -l c:license.txt (or any file you want). After setting the variable, it is recommend to reboot the machine after changing the variable.

The license.txt file can be parsed into a CSV file using lsusage.exe -l c:license.txt -c c:output.csv. More details can be found on the CDROM or downloaded media file LicenseServer/server/SysAdminHelp/index.html (About the Sentinel RMS Utilities > lsusage). The lsusage.exe file can be found on the install media for QTP under LicenseServerutils folder.