Executing powershell script via task scheduler

Hello,

I am trying to execute powershell script via windows task scheduler which will forcefully delete all email in a mailbox, but I am getting the below errors

Operational Code - 2
Task Category - Action Completed --- Task Scheduler successfully completed task "\IL98" , instance "{2b193375-cbd2-4986-918d-3cfd4027d6b6}" , action "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" with return code 0.
Last Run Result - 0X0

When I am adding additional cmdlets in the script "Set-ExecutionPolicy Unrestricted", I am getting Last Run Result 0X5 rest of the error remains the same.

Powershell version - 3.0
Task Scheduler version - 1.0

If I try to run the script manually via Exchange Powershell the script executes without any errors

Thanks in Advance,
Ankush Shah