An architectural project or engineering calculation is often months of work collapsed into a single file. In Ankara, hundreds of offices around Çankaya, Çukurambar, Söğütözü and Teknokent produce DWG, Revit and SolidWorks files every day, files that can vanish in a disk failure or a single wrong click. This guide explains, with technical accuracy, what to do and more importantly what not to do when a CAD or project file is lost.

Quick Answer

If you have lost a project file, stop working first. Do not write new data to the disk, do not install recovery software on that drive, and do not struggle on the only copy yourself. If the disk shows physical symptoms, power it off and bring it to a professional lab. Corrupted DWG or Revit files that will not open can also be recovered in most cases.

Why Project Files Are Irreplaceable

The construction drawings of a housing project, the structural calculation of a bridge, or the mechanical layout of a factory represent weeks or months of accumulated work. Losing these files is not just losing a file. Deadlines slip, tender processes stall, progress payment (hakediş) records go incomplete, and client trust is damaged.

Another characteristic of CAD and BIM files is that they depend on each other. A Revit project only makes sense together with its linked models, families and render files. An AutoCAD drawing relies on external reference (XREF) files, fonts and linetype definitions. Corruption of a single master file often renders the entire project package unusable.

The Most Critical File Types

The file types we most frequently recover for architecture and engineering offices in Ankara include:

  • AutoCAD drawings (DWG, DWT templates, DWS standards, BAK backups and temporary autosave files)
  • Autodesk Revit models (RVT projects, RFA families, RTE templates, local and central model copies)
  • SketchUp models (SKP and automatic SKB backups)
  • SolidWorks parts, assemblies and drawings (SLDPRT, SLDASM, SLDDRW)
  • ArchiCAD project files (PLN, PLA archives, BIMcloud local cache)
  • 3ds Max scenes and render outputs (MAX files, EXR and TIFF render layers)
  • Laser scan point cloud data (RCP, RCS, LAS, E57 formats, often tens of gigabytes)
  • Progress payment, tender and quantity takeoff files (Excel, PDF and proprietary databases)
  • Project archives and compressed delivery packages (ZIP, RAR)

Typical Loss Scenarios

Data loss does not always arrive with a dramatic failure. Most of the time it starts unnoticed in the middle of an ordinary workday.

Workstation SSD or HDD Failure

CAD and render workstations work hard. Under constant read and write load, the controller chip or NAND cells of an SSD weaken over time. Mechanical drives suffer head crashes, motor seizure or accumulating bad sectors. The disk suddenly disappears from BIOS or Windows hangs on boot. Trying to restart the disk repeatedly can multiply a mechanical fault and cause permanent loss.

Accidental Deletion or Overwrite

This is one of the most common scenarios. A folder is deleted by mistake, an old version is copied over a new one, or the wrong file is chosen during Save As. A deleted file does not disappear immediately, it stays on disk until its space is reused. So the moment you notice the deletion, stopping all writes to that drive dramatically improves the chance of recovery.

Corrupted DWG or Revit File

The file is on disk but will not open. AutoCAD tries to recover it and fails, or Revit reports that the file is corrupt. This usually results from an interruption during saving, a dropped connection while working over the network, a full disk, or an incomplete synchronization. In such logical corruption, the internal structure (header, object tables, indexes) is damaged. In most cases the intact portions can be parsed out and a large part recovered.

RAID or NAS Project Server Failure

Most offices keep their project archive on a shared NAS or RAID array. A second disk failing in a RAID 5 array, the wrong disk being pulled during a swap, a failed controller card, or an interruption during a rebuild can make the whole array inaccessible. RAID recovery requires expertise, and a wrong rebuild attempt can overwrite the data.

External Project Drive Failure

External drives and USB sticks carried between the site and the office often fail due to impact, drops and unsafe removal. The USB bridge board can fail or the drive can take physical damage from a fall. The risk multiplies when these drives hold the only unbacked copy of a project.

First Step by Scenario

The table below summarizes the first step to take based on file type and loss scenario.

File Type and Software Loss Scenario First Step
DWG (AutoCAD) Accidentally deleted Stop writing to disk, power off the PC
DWG (AutoCAD) Will not open, corrupt Make a copy, do not run RECOVER on the original
RVT (Revit) Central model corrupted Stop syncing, preserve local copies
SLDASM (SolidWorks) Assembly references lost Keep the whole project folder as one unit
PLN (ArchiCAD) Disk failure Power off the disk, do not retry boot
RAID array (NAS) Two disks failed Do not rebuild, do not change disk order
External drive Drop, physical damage Stop powering it, bring it to the lab
MAX, EXR (render) Interruption from full disk Do not clear temp folders, do not touch disk

Corrupted File or Deleted File

The recovery approach changes completely depending on whether the file was deleted or corrupted.

Deleted Files

A deleted file is removed from the file system table (the MFT for NTFS), but the content remains on disk. What matters is that the area has not been overwritten with new data. So after deletion, installing software, downloading files, or even background writes by Windows reduce the chance of recovery. The safest path is to connect the disk read only to another system, take a sector image, and perform recovery on that image.

Corrupted Files

A corrupted DWG or RVT file is fully present on disk but its internal structure is damaged. Here it is not disk recovery but file structure repair that comes into play. The object database of the DWG file or the element tree of the Revit file is analyzed, intact sections are parsed out, and a readable copy is rebuilt. AutoCAD's own RECOVER and AUDIT commands help with mild corruption, but on severe damage running them on the original file can make things worse. So the first rule is always to make a copy first.

Backup and Versioning Strategy

Data recovery is a last resort. The real win is preventing loss in the first place. For architecture and engineering offices we recommend the 3-2-1 rule.

  • Keep three copies: one working copy and two backups.
  • Use two different media: for example a local NAS and an external drive.
  • Keep one copy off site: cloud or a remote location, against fire and theft.

Versioning is also vital. Constantly saving over a single file removes any chance of returning to yesterday's intact state. File names with dates and version numbers, retaining automatic backups (BAK and SKB files), and the version history feature of cloud sync let you resolve a simple corruption before it turns into a disaster. The most dangerous habit is working on the only copy of a project. Always keep one copy untouched.

CAD and Project Data Recovery in Ankara

Ankara is one of Turkey's busiest centers for architecture and engineering. The design offices in Çankaya and Çukurambar, the large construction firms in Söğütözü, and the engineering and software companies at the METU and Hacettepe Teknokent campuses produce critical design data every day. The density of the construction sector makes progress payment and tender files just as valuable as the drawings.

At DSET, our lab is located on the Hacettepe Teknokent Beytepe campus. This puts us right inside Ankara's design ecosystem. We offer pickup and delivery to offices around Çankaya, Çukurambar, Söğütözü, Bilkent and METU. We can collect your faulty workstation disk, RAID project server or external project drive from your office and transport it safely to the lab. Being local removes shipping risk and shortens turnaround.

For general disk failures see our Ankara hard disk data recovery page, for multi-disk project servers see our Ankara RAID and server data recovery page, and for an overview of all our services visit our Ankara data recovery main page.

Frequently Asked Questions (FAQ)

My corrupted DWG will not open, can it be recovered?

In most cases yes. If the file is intact on disk but will not open, its internal structure is damaged. By analyzing the object database of the DWG file we can parse out the intact drawing data and build a readable copy. The key is to preserve the original file without altering it. Please do not run RECOVER on it repeatedly on your own.

Can I get back a project I deleted by mistake?

If you stop writing to that disk the moment you notice the deletion, the odds are very high. A deleted file remains on disk until its space is reused. Continuing to use the computer, installing software or downloading files can overwrite that space. The best move is to power the disk off and contact us.

Our RAID project server crashed, what should we do?

If more than one disk has failed in the RAID array or the array has become inaccessible, do not attempt a rebuild or reconfiguration. A wrong step can overwrite the data. Leave the disks in their original order and state and contact us. RAID recovery is a specialty that requires correctly resolving the array parameters.

Will the confidentiality of my project files be protected?

Yes. Tender, progress payment and private property projects are commercially sensitive. We process your data under a confidentiality agreement, only authorized technical staff have access, and once the work is complete copies are securely destroyed at your request.

How long does recovery take?

The time depends on the type of failure and the amount of data. Logical deletions and corrupted file repairs are often completed within one to three business days. Physical disk failures and large RAID arrays can take longer. After the initial diagnosis we give you a clear timeframe and status update.

DSET has been serving from Ankara Hacettepe Teknokent Beytepe since 2003. Our data recovery success rate is 99.4 percent. The first diagnosis is free, and if no data is recovered there is no charge. Phone: +90 536 662 38 09.

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