VBoxMange modifyhd command run error

[luckadog]

I want to compact disk images.
　　Host OS:Win7 Guest OS:Windows XP
　　VirtualBox vision:4.3.6 Disk format：VDI
　　My command is “VBoxMange modifyhd <uuid|filename> --compact”
　　This reply is”
　　VBoxMange.exe:error:Failed to create the VitualBox object!
　　VBoxMange.exe:error:Code E_INVALIDARG (0x80070057) - One or More arguments are invalid (extend info not avilable)
　　VBoxMange.exe:error:Most likely, the VirtualBox COM server is not running or to start.”
　　When my command just is “VBoxMange modifyhd”，It's reply the same.
　　I have seen the UserManual,it is helpless.
　　Who can help me to solve the problem?

[mpack]

That message usually means that the software has not been installed correctly, for the user attempting to execute the command. I.e. the software has been copied instead of installed properly, or it's been installed for the "Admin" account only.

You might find the CloneVDI tool easier and more efficient to use for this purpose. Read the release notes included in the zip.

[luckadog]

That message usually means that the software has not been installed correctly, for the user attempting to execute the command. I.e. the software has been copied instead of installed properly, or it's been installed for the "Admin" account only.

You might find the tool easier and more efficient to use for this purpose. Read the release notes included in the zip.

Thank you very much!