Microsoft Vulnerability Scanner Issue

Thanks Vorland, I thought it was just me going mad. The only other thing I thought of was if there was a firewall or watchguard appliance in between the perimeter and the on prem AD which may have been blocking something as all the other devices are on boarding with no problems its just the scanner that doesnt appear when you try and run a scan. I am still trying a few things to discount and devices that may be blocking the scanner but that wouldnt affect what you have has when it worked and now its disappeared unless there is an appliance blocking something. I was going to ask is the network a hybrid set up or purely cloud? Thanks in advance