I had to change the admin password as it had expired via RDP. The server was working fine after the change.
Later I disconnected the session, and started it again, now we are getting the following error message:
An authentication error has occurred. The Local Security Authority cannot be contacted Remote computer: **.cloudapp.net
This same error keeps coming up even after 2 server restarts. The password is defiantly correct as typing a different password gives a "Password Incorrect" error.
There is no other way for us to access this server.
I found the answer here.
Your machine should still have a local administrator account (e.g. MachineName\Administrator), in which case you can login with the administrator account. In the RDP login prompt, you'll need to put the full user account (e.g., "MachineName\Administrator" where MachineName is your computer's name, otherwise it will default to "PreviousDomainUsed\Administrator").
This happened to me with an Azure VM because the domain administrator account I was using had an expired password and the Azure VMs enforce Network Level Authentication, which prevents you from changing the password through RDP. I was able to update the password by logging into the domain controller's VM, but the VM I couldn't log into didn't receive the update because the DNS settings were incorrect. I RDP'd into the faulty VM with the local administrator account, updated the DNS settings and ran "gpupdate" in a Powershell command prompt and everything began working again.
Hope this helps.
I had same issue with local admin account and specifying user account as "machine name\Administrator" still did not work. There was only local admin account in Azure VM so I needed to solve this issue for local admin account.
I could reset password for local admin account by following step then now I can log in to Azure VM by local admin account.
- Open Azure Portal web site.
- Click "Virtual Machine" then click virtual machine name which issue having in the list.
- Dash board for selected virtual machine is shown. Then click "Reset Password".
- Following screen is displayed so specify local admin account name nand password, then click Update.
This uses the VMAccess extension to reset the built-in administrator account and reset the Remote Desktop service configuration. Learn more Mode You can perform a password reset, which will also reset the Remote Desktop service configuration, or choose to reset the configuration only.
- Reset password
- User name: If you provide a different user name, then the built-in administrator account with be renamed. Also, the account will be enabled if it's currently disabled. (The name of local admin account is shown as default)
- Password
- Confirm password
here is an answer if you need it yet.
来源：https://stackoverflow.com/questions/19951814/azure-unable-to-connect-to-rdp