Challenge


You receive the following error within moments of a job starting:

Cannot connect to the host's administrative share. Host: [VM hostname or IP]. Account: [domain\user].
Win32 error: The network path was not found. Code: 53

NOTE: This applies to both VMware and Hyper-V hypervisors.


Cause


This error means that the Veeam Backup & Replication server cannot connect to the Windows guest’s OS feature to deploy guest processing components. This path will be the ADMIN$ share (\\hostname\admin$) of the guest itself.

These components are deployed directly from the Veeam Backup & Replication server. If networking is inherently impossible to the guest from the B&R server (different networks, firewall, etc), processing protocol may require inversion (VMware only).


Solution

When this error occurs, there are a few items to go through:
 

  • Make sure the Windows time on the Veeam Backup server is the same as in the guest OS.
  • Make sure you do not have a firewall in the way (you can try disabling it for testing).
  • Make sure you can connect to the admin share (for example, \\Server Name\admin$) with the same credentials as provided to Veeam Backup & Replication for VSS.
  • Make sure the VSS writers are set to automatic in the guest OS.
  • Make sure you provide Local Administrator (MACHINE\Administrator) or Domain Administrator (DOMAIN\Administrator) account privileges.
  • Make sure the guest OS is in the same network as the Veeam Backup server.
  • Make sure File and Printer Sharing is enabled in the guest OS.
    • Once File and Printer Sharing is Enabled on the guest OS, ensure to provide permissions through Windows Firewall if applicable
  • If the guest OS is Vista/2008 or later:
    • In the Network and Sharing Center, verify that it is not set for a public domain.
    • Verify that the Remote Registry Service is started.
 

Note: As of 9.5 and later we have guest interaction proxies that deploy components: https://helpcenter.veeam.com/docs/backup/vsphere/guest_interaction_proxy.html?ver=95


More Information

To Inverse the processing protocol used (native Windows remote administration versus VMware VIX), utilize the below.
For Veeam 9.x and later the value should be created on the Guest Interaction Proxy.

o HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Veeam\Veeam Backup and Replication\
o DWORD: InverseVssProtocolOrder
o Value = 1
o To disable (default behavior), value is 0 (false)

For more information on permissions, see http://www.veeam.com/kb1788