Exporting Security Group Memberships in Batch

Did you try using /p to search a different path?

forfiles /p "d:\path\to\sql\backups" /s /m *.bak /d -4 /c "cmd /c del @path"

Also, compare the user account that the task runs as with security settings on the SQL backups folder.

Tasks can only launch interactively when you use the Run only when user is logged on option. Here's an excerpt from the Task Scheduler help file:

You can specify that a task should run even if the account under which the task is scheduled to run is not logged on when the task is triggered. To do this, select the radio button labeled Run whether user is logged on or not. If this radio button is selected, tasks will not run interactively. To make a task run interactively, select the Run only when user is logged on radio button.

I experimented a bit with psexec -i but no luck, sorry.

You can find a list of running scheduled tasks with schtasks.exe, eg:

schtasks /query | find "Running"

If you want to get a bit fancy, you could pull out the command line for each running task as well. Here's a batch file example:

@echo off
for /f "delims=," %%i in ('schtasks /query /fo csv ^| find "Running"') do (
    for /f "delims=, tokens=9" %%j in ('schtasks /query /fo csv /v /tn %%i ^| find /v "Next Run Time"') do (
        echo %%~i   %%j
    )
)