Resolved: “Windows Failed to Connect to the System Event Notification Service”
The error message “Windows could not connect to the System Event Notification Service” is one that many Windows users—especially Windows 7, 8, and 10 users—encounter from time to time. This message can appear during startup, login, or while running system applications. When this issue occurs, users may experience delayed logins, slow performance, or limited access to system features.
This guide walks you through what causes this error and presents a series of effective troubleshooting methods to resolve it.

What Is the System Event Notification Service?
The System Event Notification Service (SENS) is a vital Windows service responsible for monitoring and reporting system events such as network logon, power events, and user session changes. It communicates with COM+ Event System and other critical services.
If SENS is unable to start or function properly, various dependent services and user processes can also fail—leading to system instability or restricted access.

What Causes This Error?
The error usually stems from:
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Corrupted or disabled Windows services
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Improper permissions or corrupted user profiles
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Network configuration issues
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Group Policy settings (in domain environments)
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Missing or damaged system files
Now, let’s explore how to fix it.

Method 1: Restart the System Event Notification Service
Restarting the service is the most direct way to tackle the problem.
Steps:
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Press Windows + R, type
services.msc, and hit Enter. -
In the Services window, scroll down and find System Event Notification Service.
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Right-click on it and select Restart.
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If the option is grayed out, click Properties, and make sure the Startup type is set to Automatic.
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Click Start if the service is not running, then click Apply and OK.
Also, ensure that the COM+ Event System and Remote Procedure Call (RPC) services are running, as they are dependencies.

Method 2: Check for Corrupted System Files
Use the System File Checker (SFC) and DISM tools to check and repair corrupted Windows system files.
Steps:
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Right-click the Start button and choose Command Prompt (Admin) or Windows PowerShell (Admin).
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Type the following command and press Enter:
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Let the scan complete. If issues are found and repaired, restart your computer.
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If problems persist, use this additional command:
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After it finishes, restart your PC.

Method 3: Reset Winsock Catalog
If the error is related to network communication issues, resetting Winsock can help.
Steps:
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Open Command Prompt as Administrator.
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Type the following and press Enter:
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Reboot your system and check if the problem is resolved.
Method 4: Use the Group Policy Editor (for Domain Users)
In some cases, especially in enterprise or domain environments, a Group Policy might be interfering with the service.
Steps:
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Press Windows + R, type
gpedit.msc, and press Enter. -
Navigate to:
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Double-click Always wait for the network at computer startup and logon.
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Set it to Enabled.
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Click Apply, then OK.
Reboot your PC and check if the error goes away.
Method 5: Re-wp-signup.php DLL Files Related to SENS
If DLL files required for SENS are unwp-signup.phped or corrupted, re-wp-signup.phping them may fix the issue.
Steps:
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Open Command Prompt as Administrator.
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Run these commands one by one:
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Restart your system.
Method 6: Create a New User Profile
A corrupted user profile may prevent services from loading properly during logon.
Steps:
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Press Windows + I to open Settings.
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Navigate to Accounts > Family & other users.
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Click Add someone else to this PC and follow the prompts.
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Sign out and log in with the new account to see if the issue persists.
If the new user profile works, you may consider transferring your data to the new profile.
Method 7: Perform a Clean Boot
Performing a clean boot helps identify third-party software that might be interfering with system services.
Steps:
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Press Windows + R, type
msconfig, and hit Enter. -
Under the Services tab, check Hide all Microsoft services, then click Disable all.
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Go to the Startup tab and click Open Task Manager.
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Disable all startup items.
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Click OK and restart your PC.
If the error disappears, you can re-enable services and startup apps one at a time to find the cause.
Method 8: Check Event Viewer Logs
You can use Event Viewer to get more details on what caused the SENS failure.
Steps:
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Press Windows + X, choose Event Viewer.
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In the left pane, expand Windows Logs > System.
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Look for errors around the time of the message “Windows could not connect to the System Event Notification Service”.
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Note the Event ID and any service or DLL mentioned.
This information may help you target a specific fix.
Conclusion
While the “Windows could not connect to the System Event Notification Service” error might seem alarming at first, it can usually be resolved with a combination of basic troubleshooting steps—like restarting services, scanning for corrupted files, and adjusting settings.
If you continue to experience issues even after applying the fixes above, consider performing a system restore or, as a last resort, a Windows repair install.
