I have 3 Windows 10 Professional licenses (Yes, paid licenses). 2 of the licenses are used in two hardware devices & the 3rd one I am using with a VirtualBox VM machine.
My semi server class desktop computer at home has approximately 4.5T storage, consolidated from different disks. My Windows10 VM is frequently factory reset to try out different software (Mostly Oracle software at uncertified environments) & the particular partition on which I had the VM was running out of space & I planned to move the VM & the disks to a different partition with bigger free space.
Scenario: Move “Windows 10” VM from L: drive to M: drive
My nightmare started when the copy process stopped abruptly with Windows popping an error window stating there were read errors while copying disk1.vdi & I attempted again to realize that the disk1.vdi is has bad sectors or clusters.
I hurried to confirm that the VM is still accessible by restarting the VM couple of times & to my greatest pleasure the VM did start, did shutdown properly and I was able to access the Oracle database installation.
A quick googling suggested that an attempt to repair the hard disks using “CHKDSK”, the old utility could fix the .vdi corruptions & without wasting more time I jumped in
At an elevated command prompt issued the command
> chkdsk L: /F
My partition is of 1TB & after 15-16 minutes the chkdsk completed with few messages like fixing some cluster information.
I tried to copy the disk1.vdi once again to M: drive, and this time the copy process managed almost 19GB out of 29.1GB and against present me the read error.
Now, I was left with just one more option in front of me & it was to attempt recover the bad sectors, and there were chances that my virtual disk may get corrupt if the damages are more in numbers. knowing my VM is already Activated by Microsoft, I could try to reinstall Windows in a new virtual disk and retain the license as long as I am still using the other VM files as the id of the machine registered with Microsoft.
Please be informed, if you copy ONLY the vdi file, the activation will be nullified and you will be prompted to activate the copy of the Windows as soon as you start the new VM built using the copied VDI file!
So I proceeded to
>chkdsk L: /F /R
Windows suggested that it may take around 6 hrs for the repair process & I woke up next day morning to read multiple status messages about moving the corrupt sectors to new positions & some errors those could not be repaired.
I hurried to copy the disk once again & even though it seemed like forever, finally I was able to copy the disk1.vdi to M: drive!
So if you ever come across such a situation, give the above a try. If you are not cursed, most probably you will able to recover the virtual disk.