You may meet problem while creating new Hyper-V server in Windows 2008 server.
Step by Step Guide
1) Right click the folder name and select Properties and select Security tab in the new window.
You should have created a folder for the new Hyper-V server to host the VHD image file.
2) Select Virtual Machines and click Edit.
3) Check the box Full Control and remaining boxes under Allow
4) Click Apply.