The fileSyncDll.ps1 is not digitally signed. You cannot run this script on the current system.

https://www.opentechguides.com/how-to/article/powershell/105/powershel-security-error.html

Set-ExecutionPolicy

Set-ExecutionPolicy -ExecutionPolicy RemoteSigned

Unblocking a File that was downloaded

When the execution policy is RemoteSigned, the files that are downloaded from the internet (or from emails) are blocked to protect your running unsafe scripts. If you trust the contents of the script are safe then you can unblock it to run on your session using the Unblock-File cmdlet

PS C:\> Unblock-File -Path C:\Downloads\script1.ps1

Once you have changed the Execution policy permanently or temporarily for a session or a particular script you can continue to run the script but before you do that make sure the contents of the script does not harm your computer