it was because not enough free space in VM. what i did (for beginners like me)

i am using VMWare Workstation 6.2.4, shutdown Windows OS, click on Edit virtual machine settings, click on Hard Disk, on right panel clicked on Defragment button (this will take some time to done), then clicked on Compact button, this way i recover all unused space, when finished, clicked on Expand to add some space in virtual HDD, then started VM, used Disk Management feature of Win 10 and Extend C: partiion with unallocated space. shutdown and start VM, wait for Odoo server and PostgreSQL server to start, run browser, access odoo frontend with database manager and restore, the time to restore depends on the size of DB. and all done successfully.

regards