Problem with dual boot (WOA-Deployer-Lumia) Lumia 950 XL

[skrovnoCZ]

Hello. I was experimenting with my Lumia 950 XL and I was trying to dualboot Windows 11. I'm not sure why, but everytime I click on "Check status" button in "Dual BOOT" section, I get an error saying:

[Error] An error has occurred
System.ArgumentNullException: Value cannot be NULL.
Parameter name: paths

(I'm in Mass Storage mode)

_

I was looking into the code and when I was tracking the initialization of the phone's storrage, I fonud this part:

public static string CombineRelativeBcdPath(this string root)
{
return Path.Combine(root, "EFI", "Microsoft", "Boot", "BCD");
}

For whatever reason the "root" variable is null so it throws an exception. What may be causing this.
Before it happens, it is getting the information here:

public async Task<IList> GetPartitions()
{
var results = await PowerShellMixin.ExecuteScript($"Get-Partition -DiskNumber {Number}");
...
return partitions.ToList();
}

_

It is getting some info about eMMC and drive number but then it throws the null path exception.

I was trying it on multiple computers and I also reinstalled the phone using WDRT but the WOA is still throwing this error.
I also have Lumia 950 but I'm experimenting with 950 XL because it is faster. (And in pretty bad shape like scratches etc. so that is also why I'm experimenting with the 950 XL)

I'm not a professional in programming or something so I'm unable to find the problem. (Also most of the time I'm working with C++ so I forgot C#)

Any idea what may be causing this?
Thanks.

[skrovnoCZ]

Maybe I think that the problem may be on my side so I will try it next day. It also may be because of the phone being in bad condition.

[skrovnoCZ]

I've finally fixed it. Looks like that every tutorial that I was following was missing one step. Now it seems to work. Sorry for the confusion.
(Please delete this thread if needed)