Apple iMacs are widely used by professionals, including architects and designers, for their high performance and reliability. However, when a Mac displays “Error Code -36” while copying files, it typically indicates data corruption, bad sectors, or file system damage.
This case study details how we successfully recovered AutoCAD drawings and project files from an iMac hard drive that was experiencing Error Code -36, preventing file transfers.
As Ireland’s oldest and most experienced data recovery company, we applied advanced HFS+/APFS file system repair techniques to retrieve the missing architectural files.
The Challenge: Mac Showing “Error Code -36” While Copying Files
An architect contacted us after experiencing file transfer issues on their iMac. The reported symptoms included:
- “Error Code -36” when copying or opening AutoCAD (DWG) files.
- Slow file access and occasional system freezes.
- Files becoming inaccessible, appearing blank, or not responding.
- macOS Disk Utility failing to repair the drive, preventing normal fixes.
Since the iMac contained years of architectural projects, a secure and professional data recovery solution was required.
Diagnosis & Evaluation
When the iMac hard drive arrived at our cleanroom facility, we conducted a full hardware and software diagnostic. Our findings:
- Bad sectors on the hard drive – Some areas of the disk containing AutoCAD files were physically damaged.
- Corrupt HFS+ file system – macOS could not properly access certain file blocks, leading to Error Code -36.
- Fragmented and partially overwritten data – Some AutoCAD drawings were missing pieces, making recovery more complex.
Because the iMac’s hard drive was still functional but had significant corruption, a forensic recovery approach was necessary.
The Recovery Process
1. Cloning the Drive to Prevent Further Damage
Since the hard drive had bad sectors, we:
- Created a sector-by-sector clone to avoid further data loss.
- Used advanced imaging tools to read around the bad sectors and recover maximum data.
2. Repairing the HFS+ File System & Extracting Corrupted Files
Once we had a full image, we:
- Rebuilt the HFS+ catalog file, allowing macOS to recognize missing AutoCAD drawings.
- Extracted partially corrupted DWG files, ensuring they were readable.
- Used file carving techniques to reconstruct fragmented data.
3. Verifying & Restoring AutoCAD Drawings
After recovering the data, we:
- Repaired corrupted DWG files to ensure they opened in AutoCAD.
- Verified all project files for accuracy and completeness.
- Transferred the restored data to a secure external drive for the architect.
The Results: 98% Data Recovery Success
Thanks to our HFS+ repair and data extraction techniques, we successfully recovered 98% of the architect’s AutoCAD project files, including:
✅ DWG and DXF files for architectural designs
✅ Blueprints, floor plans, and 3D modeling data
✅ Client presentations and construction documentation
The architect was relieved to have their projects restored, avoiding costly rework.
Why Choose Us?
With 25 years of experience and tens of thousands of successful recoveries, we are the leading Mac data recovery experts in Ireland and the UK. Our expertise includes:
✔ Mac “Error Code -36” resolution & file corruption repair
✔ HFS+ and APFS file system recovery
✔ AutoCAD file restoration & engineering data recovery
✔ Secure & confidential data retrieval for architects and designers
If your Mac is displaying “Error Code -36,” files are not opening, or your drive is failing, don’t attempt DIY fixes—contact us for professional data recovery.