XCRDutil

Manage mounting of XVD/XVC files in HostOS, from SystemOS.

Xcrdutil can be used to get info about XVD files (and other formats) as well as mount and create XVD files with some limitations. Via the UWP sandbox, two different XVD files can be mounted, "Updater.xvd" and "SystemTools.xvd".

The tool is located at C:\Windows\System32\xcrdutil.exe

Accepted paths

XCRDutil allows specifying remote paths, in HostOS, via two notations:

XCRD paths (see below, e.g. [XUC:]\package.xvd for User Content partition in HostOS). These paths are an abstraction to the HostOS filesystem, allowing to refer to .xvd's without knowing their exact location, and possibly also allowing for security / permission checks.
Global paths (e.g. \??\F:\ for F: / XBFS drive in HostOS). These refer to a physical volume (like a disk partition, the flash, etc) in HostOS.

Not all the options/arguments for XCRDUtil expect the same format for the paths. Some options are able to work with paths pointing to the SystemOS's filesystem, while others may only work with remote paths to HostOS, in either one of the two types just specified previously:

XCRD paths.
Global paths pointing to a HostOS volume, which start with the non-standard \\??\\ prefix

Following is a table describing what options XCRDUtil has, and kind of path each option expects. Examples are provided at the end of the page:

Option	Option description	Arg1 Path type	Arg2 Path type
write_blob	Writes the contents of an .xvd (from a SystemOS path) to an .xvd in the HostOS's filesystem, represented by a XCRD path	XCRD	SystemOS
read_blob	reads one .xvd (from a HostOS XCRD path) and writes it to SystemOS's filesystem.	XCRD	SystemOS
QueryInfo	Gives information about an XVD (either mounted or unmounted) accesible to HostOS	Global HostOS path / XCRD	N/A

To be completed.

XCRD paths

XCRD Id	XCRD Path	Description
0	[XTE:]	HDD Temp
1	[XUC:]	HDD User Content
2	[XSS:]	HDD System Support
3	[XSU:]	HDD System Image
4	N/A	N/A
5	[XFG:]	HDD Future Growth
6	N/A	N/A
7	[XTF:]	XTF Remote storage
8	[XBL:]	Xbox Live storage
9	[XOD:]	XODD (System VM)
10	[XVE:]	Used for so-called "paths to embedded XVDs"
11	[XT0:]	USB Transfer Storage
12	[XT1:]	USB Transfer Storage
13	[XT2:]	USB Transfer Storage
14	[XT3:]	USB Transfer Storage
15	[XT4:]	USB Transfer Storage
16	[XT5:]	USB Transfer Storage
17	[XT6:]	USB Transfer Storage
18	[XT7:]	USB Transfer Storage
19	[XE0:]	USB External Storage
20	[XE1:]	USB External Storage
21	[XE2:]	USB External Storage
22	[XE3:]	USB External Storage
23	[XE4:]	USB External Storage
24	[XE5:]	USB External Storage
25	[XE6:]	USB External Storage
26	[XE7:]	USB External Storage
27	[XBX:]	XBOX (Copy-Over-LAN)
28	[XSR:]	SRA (local or SMB)
29	[XFA:]	Unknown
30	[XAS:]	N/A
31	[XRT:]	N/A
32	[XRU:]	N/A
33	[XRS:]	N/A
34	[XRI:]	N/A
35	N/A	N/A
36	[XCC:]	N/A

Examples

Create new XCRD Path in the HDD Temp partition

xcrdutil -bxp 0 mytestpath

Outputs something like:

Successfully built XCRD Path: [XTE:]\mytestpath
Command completed successfully.

So called "paths to embedded XVDs" can also be created

xcrdutil -bxp 0 mytestembeddedpath -exvd_path

Outputs something like:

Successfully built XCRD Path: [XVE:]\[XTE:]\mytestembeddedpath
Command completed successfully.

Mount package

xcrdutil -m [XUC:]\targetPackage.xvd

Outputs something like:

Successfully mounted [XUC:]\targetPackage.xvd
Device Path : \\?\GLOBALROOT\Device\Harddisk21\Partition1
Command completed successfully.

Mounted XVD's can be accessed with junctions:

mklink /j D:\Folder \\?\GLOBALROOT\Device\Harddisk17\Partition1\

Query Info for given XVD:

xcrdutil -QueryInfo \??\F:\host.xvd 5

Write file to Host layer

xcrdutil -write_blob [XUC:]\targetPackage.xvd D:\DevelopmentFiles\localPackage.xvd

Read file from Host layer

xcrdutil -read_blob [XUC:]\targetPackage.xvd D:\DevelopmentFiles\localPackage.xvd

Delete file on Host layer

xcrdutil -delete_blob [XUC:]\targetPackage.xvd

Error Codes

Error Number	Meaning	Description	How to obtain it
0x80070002	File/path not found	This error appears whenever an invalid path to a file is used (either XCRD, native \??\ path, or SystemOS path).	`xcrdutil -m [XUC:]\idontexist.xvd`
0x80070570	Possible permission error	This error appears when an operation is denied due to insufficient permissions. Examples include trying to mount host.xvd.	`xcrdutil -m \??\F:\host.xvd` or `xcrdutil -QueryInfo \??\F:\host.xvd 3`
0x8007048F	Path not found	This error appears when trying to create/access a file in a XCRD path that does not exist.	`xcrdutil -c [XE0:]\someinvalidpath`
0x80070032	Unknown	Possibly meaning the passed XVD does not have region information	`xcrdutil -Specifiers [XUC:]\someXvdYouveMounted`
0x80070005	Unknown	Unknown	`xcrdutil -read_blob \??\F:\host.xvd D:\DevelopmentFiles\host.xvd.dmp` (as elevated admin account)

NOTE: It is possible that error codes have changed over time with newer xcrdutil versions, and the table might not be completely accurate.

Authors: Mezone, Torus, tuxuser