47738: Acronis Backup for VMware 9: Application-aware Backup Fails on Application Detection during Execution of GuestAgent.vbs Script

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Applies to: 

Operating Systems: 

Last update: 26-05-2015

This article applies to:

  • Acronis Backup for VMware 9


1. Application-aware backup fails with an error similar to "Failed to execute agent 'cscript /NoLogo GuestAgent.vbs' with parameters '{}'."

2. Creation of an application-aware backup task fails on application detection with "Error occured loading applications over VM-Proxy" and "Failed to execute agent 'cscript /NoLogo GuestAgent.vbs' with parameters '{}'."


Execution of GuestAgent.vbs on the guest VM during application detection fails due one of the following reasons:

1. User's tmp folder is on a non-system disk.

According to http://technet.microsoft.com/en-us/library/cc722177%28v=WS.10%29.aspx changing user profile to another drive is unsupported by Microsoft and is unsafe (it breaks upgrade). Solution is to change the TMP+TEMP variables back to system drive C: Start->Computer->Properties->Advanced system settings->Environments variables...->set pathes for TMP+TEMP to default. Make also sure that: My Computer->Properties->Advanced->Environment Variables-> %PATH% variable contains "C:\Windows\System32\".

2. UAC is enabled on the guest VM

As solution UAC has to be disabled or UAC agent (vmProtect Windows Agent) must be installed inside the VM.

3. Antivirus software is blocking script execution

Disable your AV-software and re-check backup/task creation. As solution disable or configure AV software, so that it does not block script execution.

4. Manual execution of the script fails too and results 'Error: CScript Error: Can't find script engine "VBScript" for script "C:\AcronisTemp\GuestAgent.vbs"'

The cause is that AV software is replacing default system variables (PATH). As solution apply http://www.sevenforums.com/windows-updates-activation/196011-cscript-error-can-t-find-script-engine-vbscript-alternate-solution.htm .

More information

If none of the above solutions helps, please collect the following information and contact Acronis Support team:

  • vmProtect logs
  • AcronisInfo from guest VM
  • output file of the manual execution of the attached GuestAgent.zip on guest VM: cscript c:\AcronisTemp\GuestAgent.vbs > out.txt
  • ProcMon Log created during manual script execution