Shadow copy directory in inconsistent state after reboot

(Reported by @richardd2 here: https://github.com/dotnet/AspNetCore.Docs/issues/23733#issuecomment-1309996000)

We have a Windows Server 2019 VM hosting (currently) 15 instances of an API, all based on identical code. They're all configured with separate AppPools, all set to "no managed code", and all configured for shadow-copying.

```xml

```

ANCM version is 16.0.22232.9.

Mostly this works fine. But for the last two months, when the server reboots to install updates, one AppPool seemingly chosen at random ends up with its shadow copy being corrupted. Specifically, the `.deps.json` file is filled with nulls, and the main assembly `.dll` is 0kb in size. There are three errors logged in the application event log by the ANCM:

> 1027: Unable to locate application dependencies. Ensure that the versions of Microsoft.NetCore.App and Microsoft.AspNetCore.App targeted by the application are installed.

> 1027: Could not find 'aspnetcorev2_inprocess.dll'. Exception message:
> A JSON parsing exception occurred in C:\inetpub\Instance\shadow\api\99\Assembly.deps.json, offset 0 (line 1, column 1): The document is empty.
> Error initializing the dependency resolver: An error occurred while parsing: C:\inetpub\Instance\shadow\api\99\Assembly.deps.json

> 1010: Failed to start application '/LM/W3SVC/9/ROOT/api', ErrorCode '0x8000ffff'.

After stopping the affected AppPool, deleting the shadow folder, and starting the AppPool again, everything springs back into life.

There don't appear to be any other relevant events in the event log around the time of the restart.

I don't know whether this is a bug in the .NET 6 shadow copying option, or a problem with the VM, or whether something else is interfering when the server restarts.

Has anyone else seen this, or have any suggestions on how to diagnose and/or fix it? _(The debug file won't help, since the issue occurs before the application has a chance to start.)_

_Originally posted by @RichardD2 in https://github.com/dotnet/AspNetCore.Docs/issues/23733#issuecomment-1309996000_