The log file extension can be modified from .log to .txt by going to the Configuration shortcut in the JAMS Client.
In Configuration, find the DefaultLogLocation setting
Double-click this setting to access its properties
Go to the Value tab
Change C:\ProgramData\JAMS\Logs\ to C:\ProgramData\JAMS\Logs\.txt and save the setting.
The next time Jobs are scheduled to run, their log files will be in .txt format instead of .log. If the Jobs are still in the Timed Jobs or Pending Jobs areas of the Monitor View, they will run and have a .log format file.