Troubleshoot FSLogix Profile Mount Errors

If users receive "The user profile failed to attach" FSLogix error when logging in, follow these troubleshooting steps. 

• Log into the desktop and wait until you see the above error.
• Press CTRL-SHIFT-ESC to open Task Manager, go to File>Run new task and type in explorer.exe and click OK.
• Using the new File Explorer window browse via UNC this location on FS01 \\FS01.nerdio.int\Profiles\ (Be sure to swap nerdio.int for your chosen internal nerdio AD domain name.)
• If you are able to browse to the path, try creating a folder in that location.  If unable to, then Share or NTFS permissions are incorrectly set.
  • Set SHARE permissions to Everyone or Authenticated Users - Full Control
  • Set NTFS permissions per Microsoft guidance - https://docs.microsoft.com/en-us/fslogix/fslogix-storage-config-ht
• If you are NOT able to browse to the path then either the path, name resolution or networking is incorrectly specified.
  • Verify that you can browse to the path from another computer
  • In Task Manager>File>Run new task, type cmd.exe and click OK.  Ping the hostname and make sure it resolves and replies.
• If you ARE able to browse the path and created a folder then verify that the user's profile VHD(X) file isn't locked by another session.  By default, FSLogix profiles are configured to be exclusively locked by the first session that mounts the profile.  If a user is already logged into another host pool then the profile is locked.  Concurrent access to profiles is supported by FSLogix but there are trade-offs to consider.  You can find more information from Microsoft in this KB.