Unable to RDP to Azure VM is a very common issue faced by many people worldwide. If you have installed the terminal services or RDS the RDP issue is more common. As per Microsoft there are multiple troubleshooting steps mentioned in the troubleshooting session. And here is the list.
- Reset Remote Desktop configuration.
- Check Network Security Group rules / Cloud Services endpoints.
- Review VM console logs.
- Reset the NIC for the VM. (If required remove NIC and assigned new NIC)
- Check the VM Resource Health.
- Reset your VM password.
- Restart your VM.
- Redeploy your VM.
Fig: How to redeploy an Azure VM
However out of the 7 issues mentioned here the number 8 issue is highly popular and works in most of the cases.
Scenario: The VM’s are up and running in the portal and users were unable to RDP. The reason is after the Windows March 2018 patching in some Windows 2008 SP2 non R2 VM RDP didn’t worked.
Why the redeploy of the Azure VM will resolve the issues?
When we redeploy a VM in Azure it moves the VM in a new node in the Azure infrastructure, and powers it back. The redeployment of the VM retained all your configuration options and associate resources.
If you are using a static IP the redeployment will move the VM to a different host and the IP will remain the same.
If the issue still not resolved?
However if the issue is still not resolved please open a case with MS and ask them to clone this VM and mount it on another test VM with Hyper-V enabled. After that they can able to remove some registry settings and need to completely uninstall the March update. After that VM should be accessible to the network.
Windows March 2018 update (patch (KB4088878 and KB4088875) is causing RDP session failures in many Azure VM’s with Windows 2008 SP2 and few issues were also reported from Windows 2012 VM’s as well. The NIC didn’t work after the update which is the most common cause of this problem.
More update is available here.