The Ava to McKesson NHS ESR interface provides a comprehensive set of cross checks to ensure that the two systems accurately map employees to each other. This is essential to ensure employees are paid at the correct rates for the right jobs. One of the checks will produce an error "Employee payroll ref not set" when an incorrect mapping has occurred. This article discusses how to check for this and correct the employee mapping.

Poweshell is a very usefull utility, it is basicall a comand line utility that understands dot net.

To get started this walk through is excellent

https://www.darkoperator.com/blog/2013/3/5/powershell-basics-execution-policy-part-1.html

also

https://gallery.technet.microsoft.com/scriptcenter/Self-signed-certificate-5920a7c6

to create a certificate here

https://www.hanselman.com/blog/SigningPowerShellScripts.aspx

and here's the MS version

https://docs.microsoft.com/en-gb/powershell/scripting/getting-started/fundamental/using-windows-powershell?view=powershell-5.1