Notes about the QPL file extension:
Incorrect file associations could be the result of underlying issues within your PC system. As such it is highly recommended to scan your PC for invalid registry entries
, unused processes and other unfavourable system settings to identify slowdown issues.
The QPL file type is primarily associated with 'KaleidaGraph' by Synergy Software. (Macintosh file type QPLY) KaleidaGraph contains the toolset you need to do graphing and data analysis.