Several end-users try and log into their Windows 7 machine, they get a message, "failed to connect to the windows notification service" and it goes to a black screen and never actually loads their desktop. This has been going on for 6+ months.

If I promote that user to a local administrator they can log in but loose Aero Desktop Theme. It also takes minutes for the computer to boot to the desktop, and the following error is displayed:


There are a few posts that I have gone through to try and resolve the issue. Here are some of the steps I have tried to no avail.

incoming brain dump

  1. Ran netsh winsock reset
  2. Disable all non-Windows services
  3. Disable all startup apps with msconfig
  4. Uninstall Symantec Antivirus
  5. I thought it was Nvidia driver related (Dell laptops) but I just had two people that have Intel Graphics.
  6. Safe-mode boots cleanly and fast.
  7. Machines are all in the same OU. Moved problem machines to an OU with different GP and ran GPUPDATE. No change.
  8. The problem goes away on its own, from 30 minutes to 2 days.
  9. Reinstalled NIC/Audio/Video drivers
  10. I see the event \Driver\WUDFRd failed to load for the device USB\VID_0A5C&PID_5800&MI_01\7&66de6c9&0&0001 on almost all of the problem laptops. I think it is a smartcard reader.
  11. Rebuilt the WMI repository
  12. Ran netsh catalogue reset and winsock reset
  13. Tried hotfix KB2590550
  14. Ran SFC /scannow

Today the user said there was an update after they rebooted, but that doesn't explain the last six months.

I saw this on a ntbtlog. These few drivers didn't load but the log repeats it over and over, 50+ times:

Did not load driver @oem77.inf,%staccel%;ShoreTel Desktop Sharing Accelerator
Did not load driver @oem50.inf,%isnbgm2p%;Intel(R) HD Graphics Family
Did not load driver @oem48.inf,%srl_devicedesc%;Intel(R) Active Management Technology - SOL
Did not load driver @msports.inf,%*pnp0401.devicedesc%;ECP Printer Port
Did not load driver @cpu.inf,%intelppm.devicedesc%;Intel Processor
Did not load driver @cpu.inf,%intelppm.devicedesc%;Intel Processor
Did not load driver @cpu.inf,%intelppm.devicedesc%;Intel Processor
Did not load driver @cpu.inf,%intelppm.devicedesc%;Intel Processor
Did not load driver @battery.inf,%acpi\acpi0003.devicedesc%;Microsoft AC Adapter
Did not load driver @battery.inf,%acpi\pnp0c0a.devicedesc%;Microsoft ACPI-Compliant Control Method Battery
Did not load driver @battery.inf,%acpi\pnp0c0a.devicedesc%;Microsoft ACPI-Compliant Control Method Battery
Did not load driver @battery.inf,%acpi\pnp0c0a.devicedesc%;Microsoft ACPI-Compliant Control Method Battery
Did not load driver @battery.inf,%*compbatt.devicedesc%;Microsoft Composite Battery

I feel like I have done more things but I am just at a loss. This is my first Stackoverflow post, I love you guys!


  1. Colyn1337 - I agree, I think that there is a service that hangs on boot, probably set to automatic. There is a timeout (not sure how long) and Windows waits for that timeout to happen therefore taking forever to boot. I do not know a way to log which services fail, the event viewer doesn't say anything about it.

  2. Yagmoth555 - C:\pagefile.sys

  • What's actually broken? It's possible the service can't connect right away, triggers the alert, but reconnects later. – Colyn1337 Feb 12 '15 at 21:24
  • Does tge pagingfile is on another drive than the %systemroot% and the eventlog is not redirected somewhere else ? – yagmoth555 - GoFundMe Monica Feb 13 '15 at 0:23
  • What happens if you configure the SENS service to run in its own instance of SVCHOST? You'd use the command Sc.exe config SENS Type= own (space after Type= is intentional) as explained in detail at the end of the TechNet article How to troubleshoot Service Host (svchost.exe) related problems – I say Reinstate Monica Feb 13 '15 at 14:02
  • Twisty - Awesome! I will try this as soon as I get someone with an error. Thank you this looks like it might give a clue to what is breaking. How do I put a post on hold? – Upgrayedd Feb 13 '15 at 14:28
  • No need to put your question on hold; just come back to it when you're ready to report your findings. BTW, you need to put @ in front of usernames in comments so that folks are notified of your reply. – I say Reinstate Monica Feb 14 '15 at 20:06

I had the same problem. The message "failed to connect to the windows notification service", lost Aero Desktop Theme, several minutes to boot to the desktop.
I had tried everything on this blog. The only thing that worked was when I uninstalled the KB2952664 update.

  • Thank you thank you thank you thank you. This solved the issue for one of my clients. 75 computers working great. The 76th had to ruin a Friday night. – Andrew Aug 17 '18 at 21:18

This issue magically went away when I issued new machines to our end-users. I tried almost everything I could think of, and everything you thought of. One of those weird problems that went unsolved. First in my career.

Thank you very much for your insight and help. I really do appreciate all of the hard work!


I had this "Windows could not connect to the system event notification service" problem and forced the computer to turn off. I then restarted it and logged in as Admin. When I was in there, I noticed the OS wanted me to turn it off to install updates. After that was done I could use the regular account again. It seems the OS had prepared for this update and touched some necessary file so it didn't work correctly and required of me to allow the update through the Admin account.


I have same issue in my office too.

I google the fix on web, did all the suggestions but still cannot solve the problem.

Finally, I found the solution. We uninstall Symantec Endpoint Protection (SEP) 12 and upgrade to SEP 14, then all the computer fixed.

Hope it can help.


as others said, the fix was removing KB2952664 update. i couldnt find KB2952664 update in the installed updates, so i had to install it first and uninstall it afterwards. that fixed it!


I experienced this issues on two computers that were on a domain after July 2015's recent 'patch Tuesday'. It went away after a very very long logon process. A more recent fix I have in my sight is to uninstall the KB2952664 update, based on a network admins post here: http://answers.microsoft.com/en-us/windows/forum/windows_7-performance/windows-could-not-connect-to-the-system-event/e8de1ee3-159f-4dae-9e9e-9a648cd85478?page=14

I'm currently in wait & see mode going on one week to see if it comes back...

  • Nice find. I do think it has something to do with patches as multiple machines all seem to get this error all at the same time, then long stretches of nothing. Let me know what you find. I will also remove it when another pops up. – Upgrayedd Jul 28 '15 at 18:08
  • So far so good. I haven't had any issues with user's logons for 9 months. – TheMessenger Mar 25 '16 at 23:32

For me it was caused by the Smadav antivirus program that I installed while cleaning up malware. Removing Smadav took this error away. I usually don't have issues, but perhaps I installed it while the machine was busy cleaning other things.


I was racking my brain over this for hours. Then, I thought let me run through all services see what is/isn't running. After comparing all listed services settings against on the broken pc against a working pc, there were tons of services that weren't started up.

In particular, the DHCP service wasn't running.

As soon as I started that service it pulled an IP and everything was working.

Hope this helps someone else.

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