What you’re seeing
- The new VM stops at "No boot device found", "Operating system not found" or a PXE boot attempt.
- Windows starts loading and then blue-screens with INACCESSIBLE_BOOT_DEVICE (0x7B).
- Linux guests drop to an emergency shell because the root disk cannot be located.
- The conversion or restore job reported success, yet the VM never reaches the login screen.
Common causes
Every environment is different, but these are the causes our engineers find most often:
- The original server booted with UEFI but the VM was created with legacy BIOS firmware, or the reverse.
- Windows lacks a working driver for the virtual disk controller, such as VMware Paravirtual or Hyper-V SCSI, so it cannot see its own system drive.
- A small boot or recovery partition was skipped during conversion, leaving the bootloader without its files.
- A Generation 1 versus Generation 2 mismatch in Hyper-V prevents the VM from reading a GPT or MBR disk layout.
- Vendor RAID or storage drivers from the physical hardware are still forced to load and fail inside the VM.
- Linux initramfs images or fstab entries reference disk names or UUIDs that changed in the move.
Why it matters
P2V conversions usually happen because the old hardware is failing or end-of-life, so the physical box may not be an option to fall back on. While the VM refuses to boot, the applications on it are offline, and repeated conversion attempts eat into the maintenance window. Businesses migrating accounting systems, legacy databases or line-of-business apps can face days of disruption if the boot issue is not understood. Each restart that fails also adds risk of damaging the only good copy of the data.
How AskTechGurus fixes it
Skip the trial and error. A certified engineer works on your actual system, finds the root cause, and fixes it properly.
Tell us what’s happening
Submit a ticket in about two minutes. Paste the error, describe what changed, and pick your tier. No charge to submit.
A certified engineer diagnoses it
A vetted, US-based systems engineer claims your ticket, usually within minutes during business hours, and investigates over a secure remote session you can watch and end at any time.
Fixed and verified with you
The engineer resolves the root cause and confirms with you that it’s working. You don’t just get a workaround, and you get a plain-English summary of what was wrong.
Pay only when it’s resolved
Fixed price from $99, invoiced only after you approve the fix. If it isn’t resolved, you don’t pay.
Frequently asked questions
Is our data lost if the VM won't boot?
Almost never. The disk contents are normally intact, and the problem is how the virtual hardware presents that disk to the operating system.
Does this happen with both VMware and Hyper-V?
Yes, both platforms hit the same underlying issues around firmware type, disk controllers and boot partitions, although the details differ.
Can someone help us finish the migration?
A certified US engineer can work through the boot failure with you via a remote secure session, often in a single session. You pay only when the server is up.