Remote Desktop (RDC) "couldn't connect to the remote PC because no license servers were available"

Question

So I guess the CAL grace period expired and I'd like to resolve this, but how can I login remotely? The server is a Windows 2008 R2 VM on AWS. I've already tried mstsc /admin and it does not work.

For operational reasons, I can not restart the VM now unless I know that will solve the login issue.

Any ideas?

Answer 1

AWS support provided a solution. In case anyone else needs to figure it out, for AWS, here it is:

Steps to connect to the remote registry settings of the primary server:

1. Launch a temporary instance in the same subnet (subnet-####### or Same Availability Zone) as of the problematic instance. (If there is already an instance available in same subnet we can use that as well)
2. Take the backup of the instance i-############### by creating image of the instance. This is useful in case need to revert back.
3. Stop the instance i-############### > detach the root volume of the instance as mentioned here : https://docs.aws.amazon.com/AWSEC2/latest/WindowsGuide/ebs-detaching-volume.html
4. Attach the volume as secondary volume to the instance launched in step 5. Connect to the Temporary instance using RDP.
5. Download the EC2 Rescue from the link https://s3.amazonaws.com/ec2rescue/windows/EC2Rescue_latest.zip on to the temporary instance
6. Once downloaded, extract the zip file and run EC2 Rescue application > Agree the terms and conditions.
7. Select Offline instance mode > select the attached disk > Next > click Yes for Confirmation
8. You should see the volume loaded successfully message as a popup. Click ok.

Changing the registry Values on the remote instance:

1. After completing the above steps, Leave the EC2 Rescue open and open Run and type “regedit” and click enter. It will open Registry settings for you.
2. Expand Computer >Expand HKLM  you should see EC2 Rescue registry settings
3. Expand EC2Rescue_TempSystem000 > Click Select and make sure Default has a value of “1”. If it is “2” you need to modify the appropriate Control Set such as “ControlSet002”
4. Navigate to EC2Rescue_TempSystem000\ControlSet001\Control\Terminal Server\RCM.
5. Locate the GracePeriod > right click on it > Permissions > Advanced > Change the Owner to Administrator and make sure Administrator has full permissions.
6. Delete or Rename the GracePeriod to GracePeriod.old
7. Exit the Registry
8. Exit the EC2 Rescue and make sure attached secondary disk is offline under disk management.
9. Detach the secondary volume from the temporary instance : https://docs.aws.amazon.com/AWSEC2/latest/WindowsGuide/ebs-detaching-volume.html
10. Attach the volume back again to the primary instance as a root volume as /dev/sda1 : https://docs.aws.amazon.com/AWSEC2/latest/WindowsGuide/ebs-attaching-volume.html
11. Start the Instance and you should be able to RDP to the instance as we reset the RDS CAL grace period by modifying the Registry settings