Stellar Data Recovery Main Errors – Solution

Stellar Data Recovery is a powerful tool designed to retrieve lost files from compromised hard drives, SSDs, and external storage media. While generally reliable, users may occasionally encounter specific errors due to disk corruption, system permission conflicts, or hardware connectivity issues. This guide covers the most common technical hurdles users face in 2025 and provides verified solutions to get your data back safely.

Common Errors

• Activation Error 1525 / 1526: License key validation fails due to server communication or limit issues.
• Scan Stuck at 99%: The scanning process freezes near completion, often caused by disk bad sectors.
• Drive Not Detected: The software fails to list the target drive, especially common in Windows 11.
• Recovered Files are 0 Bytes: Files appear in the result list but contain no actual data when saved.
• Crash on Launch: The application closes immediately after opening due to permission or driver conflicts.

Fix 1: Activation Error 1525 / 1526

This error typically occurs when the software cannot communicate with the validation server or detects a mismatch in the system clock. It prevents the software from switching from 'Free' to 'Professional' mode.

1. Close Stellar Data Recovery completely.
2. Right-click the date/time in your Windows taskbar and select Adjust date/time.
3. Ensure "Set time automatically" is toggled On and click Sync now.
4. Temporarily disable your third-party antivirus or firewall (Windows Defender usually does not block this, but third-party tools might).
5. Relaunch Stellar as Administrator (Right-click icon > "Run as administrator") and re-enter your key.

Fix 2: Scan Stuck at 99%

If the progress bar halts at 99%, the software is likely struggling to read a specific cluster of bad sectors. Force-quitting can cause you to lose the scan progress entirely.

1. Wait it out: For large drives (2TB+), this phase can legitimately take 2-4 hours as it finalizes the file index. Do not force quit immediately.
2. If it remains stuck for over 4 hours, click the Stop button (square icon) next to the progress bar rather than closing the window. This often forces the software to save the current results.
3. If the scan fails, use the Create Image feature in Stellar (under the 'More Tools' icon) to make a replica of the drive, then scan the image file instead of the physical disk.

Fix 3: Drive Not Detected (Windows 11)

Windows 11's stricter driver enforcement can sometimes hide external drives from third-party recovery tools, even if the drive makes a sound when connected.

1. Press Win + X and select Disk Management.
2. Locate your drive in the bottom list. If it says "Not Initialized" or "Offline," right-click the label and select Online.
3. If the drive has no drive letter (e.g., just says "Disk 1"), right-click the partition area and choose Change Drive Letter and Paths, then click Add to assign a letter like 'Z'.
4. Relaunch Stellar Data Recovery; the drive should now appear in the selection list.

Fix 4: Recovered Files are 0 Bytes

A "0 KB" or "0 Byte" file means the file entry exists in the file system table (MFT), but the actual data content is missing or disconnected. This often happens after a "Quick Scan."

1. Do not save these files; they are empty placeholders.
2. Return to the main menu and ensure Deep Scan is toggled on (bottom left corner).
3. Run the Deep Scan. This reads the drive sector-by-sector rather than relying on the file table.
4. After the scan, look in the RAW Data folder in the tree view (left panel) rather than the standard folder structure. Your files will likely be here with generic names (e.g., FILE001.jpg).

Fix 5: Crash on Launch

If the application opens and immediately closes, it is usually a conflict with display drivers or insufficient permissions to access physical disks.

1. Right-click the Stellar Data Recovery shortcut and select Properties.
2. Go to the Compatibility tab.
3. Check the box for Run this program as an administrator.
4. If on a high-resolution laptop (4K screen), click Change high DPI settings and check Override high DPI scaling behavior.
5. Click Apply and try launching again.

Prevention Tips

• Stop Using the Drive Immediately: The moment you notice data loss, stop writing new data (downloads, browsing) to that drive to prevent overwriting.
• Always Use Deep Scan for Formatted Drives: Quick scans rarely recover data from formatted disks effectively; starting with Deep Scan saves time.
• Save to a Different Drive: Never save recovered files back to the same drive you are recovering from; this will permanently corrupt the remaining hidden data.

When to Contact Support

While most errors are resolvable, certain situations require professional intervention from Stellar's lab services. You should contact support if the drive makes clicking or grinding noises (physical failure) or if the drive is not detected in Windows Disk Management at all (controller failure). Before contacting them, prepare your Order ID and a screenshot of any specific error codes (like 1525) to speed up the process.