Signing a script will make your scripts comply with all exeuction policies in PowerShell and ensure the integrity of a script. Signed scripts will fail to run if they have been modified after being signed.
Scripts signing requires a code signing certificate. Recommendations:
Read more at about_Signing @ TechNet
PowerShell has configurable execution policies that control which conditions are required for a script or configuration to be executed. An excecution policy can be set for multiple scopes; computer, current user and current process. Execution policies can easily be bypassed and is not designed to restrict users, but rather protect them from violating signing policies unintentionally.
The available policies are:
|Restricted||No scripts allowed|
|AllSigned||All scripts need to be signed|
|RemoteSigned||All local scripts allowed; only signed remote scripts|
|Unrestricted||No requirements. All scripts allowed, but will warn before running scripts downloaded from the internet|
|Bypass||All scripts are allowed and no warnings are displayed|
|Undefined||Remove the current execution policy for the current scope. Uses the parent policy. If all policies are undefined, restricted will be used.|
You can modify the current execution policies using
Set-ExecutionPolicy-cmdlet, Group Policy or the
-ExecutionPolicy parameter when launching a
Read more at about_Execution_Policies @ TechNet