Sometime it happens that your Customers complains that they are not able to connect their Windows VPS Throug Remote Desktop Protocol i.e. RDP even if the VPS is responding ping requests. The most common reason for this is that the VPS is running out of memory, check the VPS memory using Virtuozzo Power Panel and reboot the VPS if required.
But in some VPS is running fine, domains, FTP and all the services are running fine but still RDP is not connecting; Please check the following are steps which can help to diagnosis the problem.
1) Check Terminal Services are running or not. To check that first login into the VPS using command prompt of the host server and execute command net start “terminal services” and if it show the output given below than the service is already running.
C:\>vzctl enter 99999 Microsoft Windows [Version 5.2.3790] (C) Copyright 1985-2003 Microsoft Corp. C:\WINDOWS\system32>net start "terminal services" The requested service has already been started. More help is available by typing NET HELPMSG 2182. C:\WINDOWS\system32>
2) Check Remote Desktop Port. By default RDP use Port 3389 to connect the server/machines remotely. You can use command “netstat -aon |findstr :3389” to see if Port 3389 is responding or not on the VPS.
C:\WINDOWS\system32>netstat -aon |findstr :3389 TCP 0.0.0.0:3389 0.0.0.0:0 LISTENING 12308 C:\WINDOWS\system32>
If you get the above reply then the VPS is using Default RDP port (:3389) but you get following output that the RDP port has been changed by the VPS administrator
C:\WINDOWS\system32>netstat -aon |findstr :3389 C:\WINDOWS\system32>
To find the exact port you will have to execute the following commands on the command prompt of the VPS.
C:\WINDOWS\system32>tasklist /svc | find "erm" svchost.exe 324380 TermService C:\WINDOWS\system32>netstat -aon | find "324380" TCP 0.0.0.0:1050 0.0.0.0:0 LISTENING 324380
Here, RDP port has been changed from 3389 to 1050. So, try to connect the RDP using IPADDRESS:PORT
3) Check Firewall Configuration. As we have seen above that if the server is responding to port 3389 or any other port locally (inside the VPS) then there is a possibility that the firewall is blocking the access. Firewall of the VPS can be stopped using Parallel Management Console or using following commands.
C:\WINDOWS\system32>net stop sharedaccess C:\WINDOWS\system32>net stop ipnat C:\WINDOWS\system32>net stop policyagent
These Commands will stop the firewall service on your VPS.
4) Check for Virus/Infection. If the VPS is infected with Viruses or Trojans or any other malicious scripts then these script can also block the RDP access for the VPS. You can scan the VPS using Cureit anti-virus which is free and can be downloaded from http://www.freedrweb.com/cureit/.
NOTE: Make sure to mount the VPS (vzctl mount VEID) and then scan the private area of the VPS. If any viruses found by the Anti-virus the best option to get this issue fixed is to create a new VPS and copy the data (You can access the data of infected VPS while it’s mounted).
If everything seems to be fine then I would suggest to contact Parallels OR the Vendor from where you have purchased the License (they will contact Parallels on your behalf) for more help.