The default working directory for a scheduled task running as the Local System account is
Source: I just tested it by making a scheduled task, running as SYSTEM, that executed a batch file. The batch file contained the line
ipconfig > test123.txt. When the scheduled task is run, the test123.txt file appears in the Windows\System32 directory.
Secondly, I created another task, also running as SYSTEM, but this time the executable was set to
C:\Windows\System32\WindowsPowershell\v1.0\powershell.exe and the argument supplied was
C:\Users\Ryan\Desktop\test.ps1. So basically, the scheduled task was configured to run the test.ps1 Powershell script. In the Powershell script, was the line
ipconfig | Out-File .\test123.txt.
The test123.txt file once again appeared in my system32 directory when the scheduled task was run.