Synology NAS Error Code 49: How to Fix It

Medium 30-60 minutes Medium Severity Verified June 2026
Summarize with ChatGPTSummarize with ClaudeSummarize with Perplexity Add as Preferred Source on Google
Error Code
49
Brand
Synology
Product Type
nas
Severity
Medium
DIY Difficulty
Medium
Estimated Fix Time
30-60 minutes
Error code 49 on Synology NAS indicates that a virtual machine (VM) managed by Virtual Machine Manager has failed to start. This can happen due to resource conflicts, corrupted VM configuration, or insufficient storage. The steps below will help you diagnose and resolve the issue.
Ad

Tools You'll Need

How to Fix Error Code 49

  1. Check DSM Resource Monitor

  2. Verify VM Configuration

  3. Review VM Logs

  4. Check Storage Pool Health

    If replacing a drive, ensure the NAS is powered off before physical replacement.

  5. Reset VM State

  6. Update DSM and Virtual Machine Manager

    Back up your data before major DSM updates.

  7. Recreate the VM

    This will lose the VM's metadata; ensure you have a backup of important data inside the VM.

Parts You May Need

NAS hard drive (if storage pool is degraded)
Check Price on Amazon
NAS hard drive (if storage pool is degraded)
Check Price on Amazon
NAS hard drive (if storage pool is degraded)
Check Price on Amazon
NAS hard drive (if storage pool is degraded)
Check Price on Amazon
Ad

When to Call a Professional

If you suspect hardware failure (e.g., bad RAM or failing disk array) or if the VM contains critical data that cannot be recovered, contact Synology support or a data recovery specialist.

Frequently Asked Questions

What does Synology error code 49 mean?
It means a virtual machine managed by Virtual Machine Manager failed to start. This can be due to insufficient resources, corrupted configuration, or storage issues.
Can I recover data from a VM that won't start?
Yes. You can mount the virtual disk (.img or .vmdk) to another VM or use a bootable Linux ISO to access files. Alternatively, recreate the VM and attach the existing disk.
Will updating DSM fix error 49?
Sometimes. Updates can resolve bugs that cause VM startup failures. Always keep DSM and Virtual Machine Manager up to date.
How much free space do I need for a VM?
At least 10GB of free space on the storage pool where the VM resides. Also ensure sufficient RAM (typically 2GB minimum per VM).
Can I run a VM while other services are active?
Yes, but you need enough overall resources. If the NAS is near capacity, consider stopping non-essential services or upgrading hardware.

Related Error Codes