Thanks for posting on our forum!
Firstly, to better understand your production environment and what happended to your shared permission, would you please send the screenshots for the four issues you have mentioned:
- users have the PID ID and a blue question mark.
——Also click on the blue question mark to see the warning information
- I can not click advanced to turn off inheritance as it is greyed out.
- if I add a user, the check name will resolve to the correct user.
- I recently had the blue login page where I could not enter a username / password on the file server
In addition, you have depicted that you have a 2012 R2 DC and a seperate file server, so they are physical machines or VMs? Or one is physical, the other is virtual? Is your seperate file server also 2012 R2? You need to give me the illustration about your environment more in detail.
Finally, please go to %SystemRoot%\System32\winevt to find relevant logs during the period when you encountered your problem. What actions did you do before this problem occurred, like Windows Update? You are also recommended to post any error messages or codes that you can find in your logs.
Thanks for your support!
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