#1 Global Leader in Data Protection & Ransomware Recovery

Misconfigured RPC Settings cause Backup Job to fail with "Failed to prepare guest for hot backup"

KB ID: 1938
Product: Veeam Backup & Replication
Published: 2014-10-16
Last Modified: 2022-12-22
mailbox
Get weekly article updates
By subscribing, you are agreeing to have your personal information managed in accordance with the terms of Veeam's Privacy Notice.

Cheers for trusting us with the spot in your mailbox!

Now you’re less likely to miss what’s been brewing in our knowledge base with this weekly digest

error icon

Oops! Something went wrong.

Please, try again later.

Article Applicability

This KB article is specific to a scenario where Dynamic RPC ports have been customized within the registry. That customization then causes the particular error Code: 87.

The primary error in the UI, "Failed to prepare guest for hot backup," has many causes, and this article only covers one possibility.

Challenge

This KB is only relevant when all three of the following errors occur.

 

The Task Summary displays:
Failed to prepare guest for hot backup. Error: Cannot upload guest agent's files to the administrative share [\\...\ADMIN$]. Cannot copy file. Source file: [..\VeeamGuestAgent_X__.exe]. Target file: [\\...\ADMIN$\VeeamVssSupport\VeeamGuestAgent.exe]. CopyFile() failed. Win32 error:The process cannot access the file because it is being used by another process. Code: 32

 

The Task Log Contains the following:
Veeam Guest Agent is not started   at Veeam.Backup.Core.CViGuestInventoryInformer.IsEnabled()
   at Veeam.Backup.Core.CViGuestInventoryInformer.Veeam.Backup.Core.IGuestInventoryInformer.TryToInventory(CGuestInventoryInfo& inventoryInfo)
Cannot upload guest agent's files to the administrative share  [\\...\ADMIN$].
Cannot copy file. Source file: [..\VeeamGuestAgent_X__.exe]. Target file: [\\...\ADMIN$\VeeamVssSupport\VeeamGuestAgent.exe].

 

The VeeamVssSupport Service is Hung within the Guest OS

Check the VeeamGuestHelper log found in C:\ProgramData\Veeam\Backup Contains

            Updating Windows Firewall exceptions list.. Ok.
            Registering RPC protocol sequences used by the server.
            Registering RPC protocol sequences used by the server.. Failed.
ERR         Cannot register RPC protocol sequences used by the server.
ERR         Cannot force RPC run-time library to use all supported protocol sequences for receiving remote procedure calls.
ERR         RPC error:The parameter is incorrect.
ERR          Code: 87

Cause

Windows API function RpcServerUseProtseq, which is used to registers RPC endpoints, fails.

Solution

This issue occurs, when RPC settings have been customized and are not properly configured in registry.

By default the HKLM\SOFTWARE\MICROSOFT\RPC\INTERNET key does not exist, if it is presented it must have been created. Likely, it was created by someone reviewing the information found here, or another article discussing that specific registry key.


Remove RPC Customized Settings:

  1. Log on to Guest VM
  2. Open the Registry Editor (regedit)
  3. Navigate to HKLM\SOFTWARE\MICROSOFT\RPC\INTERNET
  4. Export the INTERNET key to back it up.
  5. Delete the entire INTERNET (and it's sub-keys).
  6. Reboot the Guest, run the Veeam job again
To submit feedback regarding this article, please click this link: Send Article Feedback
To report a typo on this page, highlight the typo with your mouse and press CTRL + Enter.

Spelling error in text

This site is protected by hCaptcha and its Privacy Policy and Terms of Service apply except as noted in our Privacy Policy.
Thank you!

Thank you!

Your feedback has been received and will be reviewed.

Oops! Something went wrong.

Please, try again later.

You have selected too large block!

Please try select less.

KB Feedback/Suggestion

This form is only for KB Feedback/Suggestions, if you need help with the software open a support case

By submitting, you are agreeing to have your personal information managed in accordance with the terms of Veeam's Privacy Notice.
This site is protected by hCaptcha and its Privacy Policy and Terms of Service apply except as noted in our Privacy Policy.
Verify your email to continue your product download
We've sent a verification code to:
  • Incorrect verification code. Please try again.
An email with a verification code was just sent to
Didn't receive the code? Click to resend in sec
Didn't receive the code? Click to resend
Thank you!

Thank you!

Your feedback has been received and will be reviewed.

error icon

Oops! Something went wrong.

Please, try again later.