
- Why Regular Data Recovery Tools Can’t Restore Files from RAID
- Key Information About the NAS Thecus N4350
- How to Remove Hard Disks from Your NAS and Connect Them to a PC
Why Regular Data Recovery Tools Can’t Restore Files from RAID
Conventional hard drives store user data by writing it sequentially across the disk surface, which means an entire file is typically located on a single drive. In contrast, when data is written to a RAID array, each file is split into multiple fragments. These fragments are then distributed and written in sequence across all the drives in the array. Depending on the configuration, fragment sizes can range from 2 KB to 2 MB, so every file is physically stored across several disks at once.
This approach significantly increases read and write performance — after all, writing two halves of a 1 GB file to two drives simultaneously is much faster than writing the full 1 GB to a single disk. However, this same mechanism makes file recovery far more complex.
Different RAID levels use different methods to distribute and protect data. On top of that, manufacturers like Thecus often add their own proprietary structures and variations. As a result, data can be written to disks in many different formats, and each requires a specific approach during recovery.
Are there any recommended practices for off-site backup storage to prevent complete data loss in the event of a disaster?
Yes, there are several recommended practices for off-site backup storage to prevent complete data loss in the event of a disaster. Here are some of the key practices:
- Regularly backup your data: Ensure that you have a consistent backup schedule in place to regularly back up your data. This can be done daily, weekly, or based on the frequency of data changes.
- Use multiple backup locations: It is advisable to have backups stored in multiple off-site locations. This helps to mitigate the risk of data loss in case one location becomes inaccessible or compromised.
- Choose a secure and reliable off-site location: Select a reputable and secure off-site storage provider or location. Ensure that the facility has appropriate security measures in place, such as access controls, surveillance systems, and fire suppression systems.
- Encrypt your backups: Encrypting your backup data adds an extra layer of security. Even if the data is compromised, it will be unreadable without the encryption key.
- Test your backups: Regularly test the restoration process from your off-site backups to ensure they are working correctly. This will help identify any issues or errors in the backup and recovery process.
- Implement a disaster recovery plan: Develop a comprehensive disaster recovery plan that outlines the steps to be taken in case of a disaster. This plan should include the process of restoring data from off-site backups and the roles and responsibilities of the individuals involved.
- Consider cloud backup solutions: Cloud-based backup solutions offer convenience, scalability, and redundancy. They automatically store your data in multiple off-site locations, reducing the risk of complete data loss.
- Maintain documentation: Keep detailed documentation of your backup procedures, including the location of off-site backups, contact information of the storage provider, encryption keys, and recovery procedures. This documentation will be crucial during a disaster recovery scenario.
By following these recommended practices, you can significantly reduce the risk of complete data loss and ensure that your data is protected and recoverable in the event of a disaster.
How to Remove Hard Disks from Your NAS and Connect Them to a PC
Although the NAS N4350 can be accessed over the network, you still need to remove its hard disks and connect them directly to a Windows PC. Only then can the recovery software properly scan and analyze the drives. Follow these steps:
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Power off the NAS and disconnect it from the power source.
WARNING! Before removing any drives, carefully read the device manual. Improper actions may damage both the NAS enclosure and the hard disks in the RAID array.
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Remove the hard disks one by one, gently sliding each drive out of its slot. Remember that hard disks are highly sensitive: any impact or drop can cause serious physical damage.
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Label each hard disk according to its position inside the NAS. The order of the drives is crucial for correct RAID reconstruction.
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Connect the drives to your computer. In this video, we explain which ports you can use to connect hard disks and what to do if your PC does not have enough free connectors.
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Step-by-Step Data Recovery with Hetman RAID Recovery

This program restores data from damaged RAID arrays and is fully compatible with Thecus N4350. Each hard disk in the array contains technical metadata describing how files were written. When launched, Hetman RAID Recovery analyzes this metadata, automatically reconstructs the damaged array, and provides access to its contents. After that, you can browse the recovered disk and save your files. The program can also restore files that were accidentally deleted from the network drive.
How to recover data from a Thecus
N4350 has 4 HDD slots, and it supports the following array types:
- RAID 0;
- RAID 1;
- RAID 5;
- RAID 6;
- RAID 10;
- JBOD;
NAS supports:
- EXT3;
- EXT4;
- XFS;
How to Safely Recover Data from Disk Images
This utility allows you to create a complete copy of a disk and work with the disk image instead of the physical drive. This approach helps protect your data from:
- Overwriting during the recovery process;
- Additional data loss caused by bad sectors;
- User errors.
To create a disk image, follow these steps:
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Ensure you have enough free space to store the image. Its size will typically match the size of the original disk.
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In the main window, select the target disk and choose Tools - Save Disk. You can also select multiple disks if needed.
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When the Image Creation Wizard opens, select whether you want to save the entire disk or only a specific region. Adjust the settings and click Next.

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Choose the directory where the image will be saved. You may select any available disk connected to your PC or upload the image via FTP.

Where Are the User’s Files Actually Stored?
The Thecus N4350 network-attached storage keeps OS Linux operating system files on a separate RAID 1 (mirrored) array. Usually, all NAS systems create several volumes on every hard disk, and the first of them takes up to 2 Gb of space. This is where operating system files are stored. Other volumes are united into a RAID array where user’s data is written.
RAID Recovery Software: Detailed Comparison
| Product | Operating system | RAID controller support | Supported file systems | Virtual RAID controller support | Data recovery from damaged RAID | File preview |
|---|---|---|---|---|---|---|
| Hetman RAID Recovery | Windows, Linux, MacOS | Yes, over 100 controllers | FAT, exFAT, NTFS, ReFS, APFS, HFS+, Ext4, Ext3, Ext2, ReiserFS, Btrfs, VMFS, Hikvision, XFS, UFS, ZFS | Yes | Yes | Yes |
| DiskInternals RAID Recovery | Windows | Yes, over 10 controllers | FAT, NTFS, Ext2/3/4, HFS+ | No | Yes | Yes |
| R-Studio | Windows, Mac, Linux | Yes, over 20 controllers | FAT, NTFS, Ext2/3/4, HFS+ | Yes | Yes | Yes |
| UFS Explorer RAID Recovery | Windows, Mac, Linux | Yes, over 100 controllers | FAT, NTFS, Ext2/3/4, HFS+ | Yes | Yes | Yes |
| EaseUS Data Recovery | Windows | Yes, over 20 controllers | FAT, NTFS, Ext2/3/4, HFS+ | No | Yes | Yes |
| ReclaiMe Free RAID Recovery | Windows | Yes, over 100 controllers | FAT, NTFS, Ext2/3/4, HFS+ | Yes | Yes | Yes |


Yes, data recovery from a Thecus N4350 NAS device can be performed even if there are issues with the network router or switch. The NAS device itself stores the data on its internal hard drives, so as long as the drives are functioning properly, the data can be recovered.
To perform data recovery from a Thecus N4350, you can directly connect the NAS device to a computer using an Ethernet cable. This allows you to access the NAS device and retrieve the data even if there are network connectivity issues.
However, if the data recovery process requires network access or if the NAS device is configured to use specific network settings, resolving the issues with the network router or switch may be necessary to fully recover the data.