使用Windows一段时间的人可能已经目睹了“ RPC Server is Unavailable ”错误。这是您在使用Windows 操作系统(Windows OS)时可能遇到的更常见的错误之一，并且通常会导致更多没有经验的Windows用户对它首先出现的原因感到困惑。
但是，您不必担心，因为这不是严重或危险的错误，因此您的所有程序和数据都是安全的。RPC代表的是远程过程调用(Procedure Call)，它是一些应用程序用来与在同一台计算机上运行的其他应用程序进行通信的一种方法。
这意味着RPC允许不同的进程相互通信以执行任务。
它的操作类似于网络，因为RPS服务器将打开一个端口，测量来自目标服务或服务器的响应，一旦收到响应就发送一个数据包，然后将任务数据传输到目标服务或服务器。工作完成后，整个过程反向操作，将数据发送回启动程序。
发生 RPC 服务器错误(An RPC Server Error Has Occurred)
RPC服务器错误不是Windows 操作系统(Windows OS)独有的，也不是单台计算机独有的。RPC方法用于大多数当前的操作系统。RPC错误的原因通常会发生在一台计算机上，但实际上可能会在整个网络上找到原因。幸运的是，在本文中，我们将研究这两种可能性。
那么究竟是什么导致了“ RPC Server is Unavailable”错误呢？当您计算机上的一项服务需要与另一项通信时，它会联系您计算机上的RPC服务器以启动交换。
RPC服务器将打开一些端口以侦听消息并返回。如果RPC服务器无法接收响应、无法写入内存、无法打开端口或根本不可用，则会触发错误。
修复 RPC 服务器错误(Fixing RPC Server Errors)
有三种方法可以在运行Windows 10的计算机上修复其中一个错误。三者中最常见的是RPC服务甚至没有运行。另外两个，网络问题或注册表项损坏，不太可能发生，但仍可能发生。
当您收到其中一个错误或任何Windows错误时，首先要尝试的是完全重新启动。重新启动将修复与RPC服务器相关的临时问题。如果重新启动无法解决错误，您将需要深入研究以下修复程序之一。
RPC 服务未运行(RPC Service Not Running)
重新启动后，检查RPC 服务(RPC Service)是否导致问题。
- 通过右键单击任务栏(Task Bar)并从列表中选择它来打开任务管理器。(Task Manager)
- 导航到服务(Services)选项卡，然后打开服务(Open Services)。
- 滚动到远程过程调用(Remote Procedure Call )服务。它应该正在运行并设置为Automatic。如果不是，请更改它。
- 导航到DCOM 服务器进程启动器(DCOM Server Process Launcher)。这也应该运行并设置为Automatic。同样(Again)，如果结果不同，请进行必要的更改。
网络问题(Network Problems)
TCP或防火墙的问题可能会阻止RPC工作。即使在您自己的计算机上进行内部调用也是如此，因为RPC 服务器(RPC Server)仍然使用网络堆栈进行通信。
- 拉起控制面板(Control Panel)并选择网络和 Internet(Network and Internet )（按设置为类别查看）或网络和共享中心(Network and Sharing Center )（设置为大图标或小图标）。
- 单击位于Connections旁边的Ethernet链接：然后在弹出窗口中单击Properties 。
- IPv6和Microsoft 网络(File and Printer Sharing for Microsoft Networks)的文件和打印机共享都应该有一个复选标记。如果没有，请添加它并单击“确定”，然后重试导致错误的任务。如果它们已经被标记，那么您需要检查您的防火墙。
- 在控制面板中 选择Windows 防火墙。(Windows Firewall )
- 对于第三方防火墙，您必须尝试设置。你应该给它一次，但如果它是你已经使用了一段时间的防火墙，不要改变任何东西。
- 找到远程协助(Remote Assistance)并确保已为域(Domain)、专用(Private)和公共(Public)网络启用它。然后保存您所做的任何更改。
注册表损坏和并发症(Registry Corruption and Complications)
如果到目前为止一切正常，那么您可以查看的最后一件事是控制RCP和DCOM服务是否损坏的注册表项。我不建议修改注册表，尤其是对于初学者来说，所以为了安全起见，我们将在搞砸任何事情之前备份注册表。
- 在任务栏(Task Bar)上的搜索框中输入regedit。出现时单击(Click)注册表编辑器(Registry Editor)。
- 单击左侧窗口中的计算机，然后打开(Computer)文件(File)选项卡。从菜单中选择导出。(Export)
- 选择保存文件的名称和位置，然后点击保存(Save)按钮。
创建所有注册表文件的备份后，您可以检查RPC和DCOM服务的条目。
导航到以下键：
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\RpcSs
在右窗格中，右键单击开始(Start)，然后修改(Modify)...将值设置为 ( 2 )。
接下来，您需要导航到以下两个键：
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\DcomLaunch
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\RpcEptMapper.
对Start(Start)执行与上一步中相同的操作。
How to Fix ‘RPC Server is Unavailable’ Error in Windows
Those of you who have been using Windows for some time may have already bore witnеss to the “RPC Server is Unavailable” error. This is one of the more common errors you can run into while using the Windows OS and often causes confusion to more inexperienced Windows users as to why it popped up in the first place.
You needn’t worry, however, as it isn’t a serious or dangerous error, so all of your programs and data are safe. What RPC stands for is Remote Procedure Call, which is a method that some applications will use to communicate with other applications that are running on the same computer.
What this means is that RPC allows different processes to communicate with one another in order to perform a task.
It operates similarly to networking in that the RPS server will open a port, gage a response from the destination service or server, send a packet once a response is received, and then transfer the task data to the destination service or server. After the job is done, the whole process operates in reverse to send data back to the initiating program.
An RPC Server Error Has Occurred
RPC server errors aren’t exclusive to the Windows OS nor just a single computer. The RPC method is used on most current operating systems. The cause for an RPC error will usually occur on one computer, but the cause may actually be found on an entire network. Luckily, in this article, we’ll be looking into both possibilities.
So what exactly causes an “RPC Server is Unavailable” error? When one service on your computer needs to communicate with another, it will contact the RPC server on your computer to initiate the exchange.
The RPC server will open up a few ports in order to listen for a message and issue one back. If the RPC server fails to receive a response, is unable to write to memory, cannot open a port, or is simply unavailable, then the error is triggered.
Fixing RPC Server Errors
There are three ways to go about fixing one of these errors on a computer running Windows 10. The most common of the three would be that the RPC service is not even running. The other two, issues with the network or corrupted registry entries, are less likely but may still occur.
When you receive one of these errors, or any Windows error really, the first thing to try is a full reboot. A reboot will fix a temporary issue related to the RPC server. If a reboot doesn’t resolve the error, you’ll want to dive into one of the fixes below.
RPC Service Not Running
After a reboot, check to see if the RPC Service is causing the problem.
- Open the Task Manager by right-clicking on the Task Bar and selecting it from the list.
- Navigate to the Services tab and then Open Services.
- Scroll to the Remote Procedure Call service. It should be running and set to Automatic. If it’s not, change it.
- Navigate to the DCOM Server Process Launcher. This too should be running and set to Automatic. Again, if results are different, make the necessary changes.
Network Problems
Issues with TCP or your firewall can stop RPC from working. This is true even if the call is made internally on your own computer as the RPC Server still uses the network stack for communication purposes.
- Pull up the Control Panel and select Network and Internet (view by set to Categories) or Network and Sharing Center (set to either large or small icons).
- Click the Ethernet link located next to Connections: and then Properties in the popup window.
- The IPv6 and File and Printer Sharing for Microsoft Networks should both have a checkmark. If they do not, add it and click OK and retry the task that caused the error. If they are already marked, then you’ll need to check your firewall.
- Select the Windows Firewall in Control Panel.
- For third-party firewalls, you’ll have to experiment with the settings. You should give it a once over but don’t change anything if it’s a firewall you’ve been using for a while.
- Locate Remote Assistance and make sure it is enabled for Domain, Private and Public networks. Then save any changes you have made.
Registry Corruption and Complications
If everything has been fine up to this point, then the last thing you can take a look at is the registry entries that control the RCP and DCOM services for corruption. I don’t recommend tinkering with the registry, especially for beginners, so to be safe, we’re going to back up the registry before messing with anything.
- Enter regedit into the search box on the Task Bar. Click on Registry Editor when it appears.
- Click Computer from the left side window and open the File tab. Select Export from the menu.
- Choose a name and location for the saved file and hit the Save button.
Once a back up of all registry files has been created, you can check the entries for the RPC and DCOM services.
Navigate to the following key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\RpcSs
In the right pane, right-click Start and then Modify… Set the value to (2).
Next, you’ll need to navigate to both the keys below:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\DcomLaunch
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\RpcEptMapper.
Do the same thing with Start as was done in the previous step.
