Those of you who have used Windows for a while may have already witnessed the “RPC Server Unavailable” error. This is one of the most common errors you can encounter when using the Windows operating system, and often causes confusion among more inexperienced Windows users as to why it even occurred.
However, you have nothing to worry about as this is not a serious or dangerous error, so all your programs and data are safe. RPC stands for Remote Procedure Call, a method that some applications will use to communicate with other applications running on the same computer.
This means that RPC allows different processes to communicate with each other to complete a task.
It works similar to a network in the sense that the RPS server opens a port, measures the response from the target service or server, sends a packet after receiving the response, and then passes task data to the target service or server. After the completion of the work, the entire process works in reverse order, sending data back to the initiator program.
RPC Server Error
RPC server errors are not limited to Windows or individual computers. The RPC method is used in most modern operating systems. The cause of the RPC error usually occurs on one computer, but in fact, the cause can be found across the entire network. Fortunately, in this article we’ll cover both possibilities.
So what exactly causes the “RPC Server Unavailable” error? When one service on your computer needs to communicate with another, it will contact the RPC server on your computer to initiate an exchange.
The RPC server will open several ports to listen for the message and send one back. If the RPC server cannot receive a response, cannot write to memory, cannot open a port, or is simply unavailable, an error occurs.
Fix RPC Server Errors
There are three ways to fix one of these errors on a Windows 10 computer. The most common of the three is that the RPC service is not even running. The other two, network problems or corrupted registry entries, are less likely, but can still occur.
When you get one of these errors, or any other Windows error, the first thing to try is performing a hard reboot. A reboot will fix the temporary problem with the RPC server. If restarting does not resolve the error, you should investigate one of the following fixes.
RPC service is not running
After reboot, check if the RPC service is causing the problem.
- Open Task Manager by right-clicking the taskbar and selecting it from the list.
- Click the Services tab and then open Services.
- Scroll down to the RPC service. It should be running and set to automatic. If it isn’t, change it.
- Navigate to the DCOM Server Process Launcher. It should also be running and set to automatic. Again, if the results differ, make the necessary changes.
Problems with TCP or your firewall can prevent RPC from working. This is true even if the call is made inside your computer, since the RPC server still uses the network stack for communication.
- Open Control Panel and select “Network and Internet” (browse by select “Categories”) or “Network and Sharing Center” (set for large or small icons).
- Click the Ethernet link next to Connections and then Properties in the pop-up window.
- IPv6 and File and Printer Sharing for Microsoft Networks should have a checkmark. If it doesn’t, add it, click OK and retry the task that caused the error. If they are already checked, check your firewall.
- Select Windows Firewall from Control Panel.
- For third party firewalls, you will have to experiment with the settings. You should check this again, but don’t change anything if it’s a firewall you’ve been using for a while.
- Find Remote Assistance and make sure it is turned on for domain, private and public networks. Then save any changes you made.
Registry corruption and complications
If all was well up to this point, the last thing you might want to look at is the registry entries that monitor RCP and DCOM services for corruption. I don’t recommend messing around with the registry, especially for beginners, so just in case we’ll back up the registry before we do anything.
- Type regedit in the search box on the taskbar. Click “Registry Editor” when it appears.
- Click “Computer” in the left window and click the “File” tab. Select “Export” from the menu.
- Choose a name and location for the saved file and click the Save button.
After backing up all registry files, you can check the entries for the RPC and DCOM services.
Navigate to the next key:
HKEY_LOCAL_MACHINE SYSTEM CurrentControlSet services RpcSs
In the right pane, right-click “Start” and then “Change Set to (2)”.
Then you will need to navigate to both keys below:
HKEY_LOCAL_MACHINE SYSTEM CurrentControlSet services DcomLaunch HKEY_LOCAL_MACHINE SYSTEM CurrentControlSet services RpcEptMapper.
Do the same with Start as in the previous step.