I have found a scheduler for Windows that works perfectly sliently (z-cron), apart from the maximum frequency for tasks being 5 minutes rather than the 1 minute I require.
Quick update - success.I have finally resolved this via Windows Scheduler itself.
The steps necessary are:-
1) Create the "real" batch file e.g. DOSOMETHING.BAT
2) Create another batch file that contains the single line "DOSOMETHING.BAT>nul" (no spaces) & name it something like "Run_DOSOMETHING.BAT". The >nul part forces it to not display any output, but it still pops up a black CMD window.
3) Create a shortcut to "RunDOSOMETING.BAT" that will be automatically named "Run_DOSOMETHING.BAT - Shortcut" & instruct it to run Minimized in its "Properties" tab.
That hides the pop up CMD window, but the task bar icons can still be seen expanding & contracting as the batch file(s) run.
4) Create a scheduled task to actually run
the shortcut at whatever intervals are required, but in the "Action" section enter the program as "Run_DOSOMETHING.BAT - Shortcut.lnk"
The addition of ".lnk" is necessary, otherwise the normal .BAT file will run.
If asked if you want to run the task with arguments, choose NO.
5) Choose to run the task "whether user is logged on or not", also entering your usual Windows logon password (if requested).
Job done.
The above certainly works for Windows 7, & I imagine a similar procedure will work for previous Windows versions too.
Absolutely no sign of the batch file(s) running can be seen, apart from the dates/times of the files being created/updated as output from the batch file(s) auto-updating. Even this is only visible if actually viewing the relevant folder at the time.
The scheduled task now runs as a Windows "Service" thus there is no danger of accidentally stopping it.
Paul.