Change the path variable so that the 8.1.6 bin directory is before 8.1.7 bin directory. Right-click on My Computer and select Properties. The System Properties window appears. Click theAdvanced tab. Click the Environmental Variables button. In the System Variables box, highlight Path and then select Edit. Type the full path for the 8.1.6 bin directory before the full path for the 8.1.7 bin directory.