How to Fix ‘RPC Server is Unavailable’ Error in Windows

The "RPC Server is Unavailable" error in Windows can be frustrating for users, as it often disrupts essential services and applications. This error can prevent files from being accessed, programs from launching, and can even hinder system functions, leading to decreased productivity. In this article, we will explore the causes of the "RPC Server is Unavailable" error, its implications, and comprehensive step-by-step solutions to fix it.

Understanding the RPC Service

Remote Procedure Call (RPC) is a protocol that allows a program to execute code on another computer. It facilitates communication between different processes, allowing for efficient service sharing and task execution across computers on a network. The RPC service is essential for various Windows functionalities, including file sharing, network management systems, and other essential operations.

When the RPC service on your Windows machine is not accessible, you may encounter the "RPC Server is Unavailable" error. Typical scenarios where this error manifests include:

During the installation of applications.
When trying to connect to a network printer.
While accessing shared files on a network.
When launching certain Windows features or services.

Common Causes of the "RPC Server is Unavailable" Error

Before diving into the solutions, it’s beneficial to understand what might be causing the error:

RPC-Service-Related Issues: The RPC services may be stopped or misconfigured.
Firewall Settings: Overzealous firewall configurations can block RPC connections.
Network Connectivity: Issues with network connections can lead to unavailability of the RPC server.
Corrupted System Files: Damaged or corrupted files can disrupt the operation of the RPC service.
DNS Issues: Domain Name System problems may impede the system’s ability to resolve network requests.
Malware Infections: Malware can compromise system services, including RPC, leading to errors.
Windows Updates: Pending or failed updates may affect system functionalities, including RPC services.

Steps to Fix the "RPC Server is Unavailable" Error

Now let’s delve into the detailed solutions you can implement to resolve the "RPC Server is Unavailable" error.

Step 1: Restart the RPC Services

The first and simplest step is to restart the RPC services.

Open the Services Manager: Press Win + R, type in services.msc, and press Enter.
Locate Services: Find the following services:
- Remote Procedure Call (RPC)
- DCOM Server Process Launcher
- RPC Endpoint Mapper
Restart the Services:
- Right-click on each service and select Restart.
- Ensure that the services are set to start automatically. Right-click, select Properties, and change the startup type to Automatic.

Step 2: Check and Configure Windows Firewall

Sometimes, firewalls block essential RPC traffic, leading to the error. Here’s how you can check and configure Windows Firewall:

Open Windows Firewall: Search for "Windows Defender Firewall" in the Start menu.
Allow an App Through Firewall: Click on "Allow an app or feature through Windows Defender Firewall".
Check Settings: Look for the services that might require RPC access. Ensure they are allowed through the firewall, especially programs like Remote Desktop, File Sharing, and web services.
Temporarily Disable Firewall: If unsure, you can temporarily disable the firewall for testing. Go back to the main firewall window and click on "Turn Windows Defender Firewall on or off" to assess if it resolves the issue. If it does, you’ll need to adjust your firewall settings.

Step 3: Verify Network Connectivity

RPC typically requires a stable network connection. Follow these steps to verify:

Check Connection: Ensure your device is connected to the network properly. Check cable connections for wired devices or ensure your Wi-Fi is functioning.
Ping the Server: Open Command Prompt (search for cmd and press Enter) and type:
```
ping [IP address of the network server]
```
Check for Issues: If you receive "Request timed out" messages, it indicates a problem with network connectivity.

Step 4: Update Network Driver

Outdated or corrupted drivers can lead to communication problems. Here’s how to update the network driver:

Open Device Manager: Type Device Manager in the Start menu.
Expand Network Adapters: Find and expand the "Network adapters" section.
Update Driver: Right-click on your network adapter and select Update Driver. Follow the prompts to search automatically for updated driver software.

Step 5: Run System File Checker (SFC) and DISM

Corrupted system files may also contribute to the error. You can repair these with the System File Checker tool.

Open Command Prompt as Administrator: Search for cmd, right-click, and select "Run as administrator".
Run SFC Scan: Type the following command and press Enter:
```
sfc /scannow
```
Run DISM Tool: After the SFC scan completes, run this command:
```
DISM /Online /Cleanup-Image /RestoreHealth
```
Restart Your Computer: After both scans, restart your PC and check if the error persists.

Step 6: Check the DNS Settings

DNS issues can also lead to this error. To fix DNS-related problems:

Open Network Connections: Right-click on the network icon in the system tray and select "Open Network & Internet settings".
Change Adapter Options: From the left side, click on "Change adapter options".
Modify Properties: Right-click on your current network connection (Ethernet or Wi-Fi) and select Properties.
Internet Protocol Version 4 (TCP/IPv4): Highlight this option and click on Properties.
Use DNS Server Addresses: Select "Use the following DNS server addresses" and enter Google’s DNS as an example:
- Preferred: 8.8.8.8
- Alternate: 8.8.4.4
Click OK: Save your changes and restart your computer.

Step 7: Check for Malware

Malware can interfere with RPC services. To eliminate this possibility:

Run Windows Defender: Open Windows Security and go to "Virus & threat protection". Click on "Quick scan".
Use Additional Tools: Consider using other reputable antivirus or anti-malware tools like Malwarebytes for a thorough system scan.

Step 8: Repair Windows Installation

If all else fails, repairing the Windows installation may be necessary.

Create a Recovery Drive: You can create a recovery drive on a USB flash drive using the "Create a recovery drive" tool in the Control Panel.
Boot from Recovery Drive: Restart your computer and boot from the recovery USB.
Select Repair Your Computer: Instead of reinstalling, select the option to repair your installation.
Follow Instructions: Proceed with the on-screen instructions. This may help restore missing or corrupted files necessary for proper RPC functionality.

Step 9: Update Windows

Keeping your system updated is crucial not just for security but also for functionality.

Open Windows Settings: Press Win + I.
Go to Updates & Security: Click "Windows Update".
Check for Updates: Click the Check for updates button and install any pending updates.

Step 10: Contact Support

If none of the above methods yield success, it may be time to reach out for additional support. Contact your IT department if you’re in a corporate environment, or consult Microsoft Support for further assistance.

Conclusion

Dealing with the "RPC Server is Unavailable" error can indeed be a challenging experience. However, with a systematic approach, you can effortlessly navigate through the troubleshooting process to restore functionality. By following the steps outlined in this article, you should be able to identify and resolve the underlying issues causing the RPC service to become unavailable. Regularly maintaining your system, ensuring drivers are up to date, and keeping an eye out for potential security threats are all prudent practices that can help prevent this and similar issues in the future.

Remember, in the complex world of Windows OS, patience and methodical problem-solving are the keys to success.