IIS 10 - Cannot read \\?\<EMPTY> configuration file

The issue is related to the temporary symbolic links created for the application pools by IIS/WAS being messed up during the Windows Update process for installing Fall Creators Update.

The steps to solve the problem are (at an administrator powershell):

Stop-Service -Force W3SVC
Stop-Service -Force WAS
Foreach($item in Get-ChildItem C:\inetpub\temp\appPools){
  if([IO.File]::Exists($item.FullName)){
    Remove-Item $item -Force
  } else {
    [IO.Directory]::Delete($folder.FullName,$true);
  }
}
Start-Service W3SVC 
Start-Service WAS

Deleting everything (files, folders and shortcuts) under "c:\inetpub\temp\apppools" will clear the temp files and the incorrect symbolic links, and starting IIS/WAS again should create them back and fix the issue.

Edit Microsoft have documented the issue in the following KB: https://support.microsoft.com/en-us/help/4050891/error-http-503-and-was-event-5189-from-web-applications-on-windows-10

Robson Rocha

Posted 2017-10-20T09:55:36.697

Reputation: 598

1Thank you! Not only the files stored there, but also had to delete a folder shortcut to DefaultAppPool. After that (and reconfiguring the IIS due to the factory reset I made), it's working now!! – Unapedra – 2017-10-20T14:50:09.797

1Yep, I had to delete the folder shortcuts as well. Works now! – Chris Hynes – 2017-10-20T15:28:58.073

1While I don't think it's problematic to delete all the files in appPools folder, you can just delete the subfolder of the problematic Application Pool name as indicated in the error message. – LongZheng – 2017-10-24T05:55:01.903

1@LongZheng: The problem is that, after the Fall Creators Update installation, all AppPools become problematic. – Robson Rocha – 2017-10-24T11:09:07.167

7We've hit this at Stack Overflow across so many devs and designers now. Thanks so much for posting a solution, it will save everyone here a ton of time and frustration. – Nick Craver – 2017-10-26T23:52:07.927

1Step 3 gave me a "Remove-Item : There is a mismatch between the tag specified in the request and the tag present in the reparse point" error, but I just deleted the folder manually from explorer and went ahead with 4 and 5 - then it worked as expected. – Konamiman – 2017-10-27T07:48:15.873

@Konamiman the same thing happened for me with this answer and with the steps given by Microsoft in the KB – Alec Gorge – 2017-10-27T15:47:19.827

1My original answer involved using plain old DOS commands at a command prompt. I've indeed found that in some machines the remove-item command may fail, still don't know why, but manually delete everything through windows explorer also works fine in this case, as long as IIS an their related services are stopped. – Robson Rocha – 2017-10-27T19:05:27.187

@RobsonROX In my case, I had one AppPool that became corrupt, but another one was fine. – LongZheng – 2017-11-08T23:22:19.667

Thanks for this. In my case simply deleting the temp files in C:\inetpub\temp\appPools resolved the issue after a Windows update. – Senkwe – 2018-01-05T10:35:42.753

This is documented here by this KB: https://support.microsoft.com/en-us/help/4050891/error-http-503-and-was-event-5189-from-web-applications-on-windows-10 I am curious; did you get upgraded through Windows Update offering you to upgrade with a notification? Or did you manually upgrade through other means?

– bariscaglar – 2017-10-25T00:28:15.270

@bariscaglar So far I have hit this problem using the manual installer and the windows update (not on my machine on the latter, but on a coworker) – Robson Rocha – 2017-10-27T07:36:57.203

IIS 10 - Cannot read \\?\<EMPTY> configuration file

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