Data loss -
How to act correctly
Data carrier defective? Data lost?
Keep calm. Your data is most likely still on your data medium!
The loss of data due to deleted files and software errors can be reversed in our laboratory. Even if the data medium has been damaged (water, heat, shock), data recovery is successful in 90% of all cases. Restoration takes place in a clean room.
Keep calm and act with caution
In the following articles we describe problem cases with possible measures, without guarantee for completeness and topicality.
In general, we strongly recommend that you contact us directly if you suspect data loss and refrain from attempting repairs yourself. The execution of independent diagnoses, for which a corresponding understanding of hardware and software is required, is at the user’s own risk. Datenretter Schweiz does not assume any liability for this.
Defective data carrier
Turn off the computer or external hard drive immediately and contact us. Do not switch the device on again under any circumstances and do not attempt to repair it. The hard disk must be UNCONDITIONALLY and EXCLUSIVELY opened and diagnosed in a clean room.
The probability of a defective disk is rather low, but not impossible.
If the computer has a preboot diagnostic test, run it. To do this, press the corresponding setup key (F2 for HP and Lenovo, F12 for Dell. Key variations are possible; consult the user manual or the manufacturer’s website if possible) and perform a computer diagnosis.
If the diagnostics do not give any disk errors, you can start repairing the operating system. However, act with caution and refrain from resetting the system for the time being, as this can also result in data loss.
If the diagnostic test shows that the data carrier is defective, the computer must be switched off immediately and must not be switched on again. Contact us and do not make any independent repair attempts.
If no preboot diagnostic test is available on the computer, a data medium defect should be ruled out before repairing the operating system. For this, the data medium must be removed and diagnosed offline.
Contact us or the PC specialist you trust. This has the necessary tools for a reliable disk check.
The probability of a defective data carrier or the risk of data loss must be seriously considered.
Be sure to refrain from repairing the operating system and also from performing a preboot diagnostic test (see the previous article), because during the repair or test the disk is still in operation and it can suffer greater damage in case of a defect.
The disk must be removed and diagnosed offline before performing an operating system repair.
Contact us, we will help you quickly and without complications.
If the computer does not turn on at all, the first thing to do is remove the disk and run an offline diagnostic. If it is possible to access the data medium, we recommend that you perform a manual data backup (copy-paste) immediately, even if the data medium does not contain any errors.
If the data can no longer be accessed, switch off the data carrier immediately and contact us. Do not carry out any independent repair attempts.
If the diagnostics do not give any disk errors, and after you have backed up your data offline, you can start repairing the computer.
Do not attempt to remove, clean or dry the data carrier yourself. Contact us as soon as possible and do not turn on the computer, external hard drive, NAS and generally the storage device(s) in any case.
Use your operating system’s built-in Disk Management (Windows/Linux) or Disk Utility (MacOS) to check if the disk is displayed.
If the disk is recognized, try to assign a drive letter to it. If this process takes place without error or feedback with reference to the disk initialization or assignment of a file system, you can continue with it and the disk and its contents are available to you again. Use diagnostic software to check whether the external data carrier is defective.
However, if drive assignment is made dependent on disk initialization or file system assignment before or during the process, you must cancel drive assignment immediately so that no data is deleted or overwritten. Switch off the external data carrier immediately and contact us.
If, when accessing the external data medium via the context window, you are asked whether the data medium should be formatted, be sure to answer this with “CANCEL” or close the context window. In any case, avoid formatting the disk.
Instead, use a diagnostic program to check whether the data medium has errors. Switch off the hard disk immediately and contact us if there are any disk errors. Do not carry out any independent rescue attempts.
If the error is negative, you can use data recovery software to search for lost data on the external disk. Do not perform any formatting.
Please contact us if the search is not successful or if you do not want to search your data yourself.
Deleted data
In case of deleted/disappeared data, the computer must be turned off immediately.
Do not install and transfer new software and data under any circumstances – not even data recovery programs – as this may cause disk areas to be overwritten, thus overwriting the deleted files. Also, system optimization (defragmentation, indexing, etc.) must be prevented at all costs. The data medium must not be written to again under any circumstances.
For data recovery, the disk must necessarily be removed and scanned offline for the deleted data.
Do not turn on the computer again and contact us.
In case of deleted/disappeared data, the computer must be turned off immediately.
Do not install and transfer new software and data under any circumstances – not even data recovery programs – as this may cause disk areas to be overwritten, thus overwriting the deleted files. Also, system optimization (defragmentation, indexing, etc.) must be prevented at all costs. The data medium must not be written to again under any circumstances.
For data recovery, the disk must necessarily be removed and scanned offline for the deleted data.
Do not turn on the computer again and contact us.
The external data medium or the partition must not be written to under any circumstances.
Various paid data recovery programs offer recovery of deleted data, but this requires a higher understanding of hardware and software.
Refrain from experiments and contact us. We restore disappeared partitions quickly and reliably.
The external data medium or the partition must not be written to under any circumstances.
Various paid data recovery programs offer the recovery of deleted partitions, but this requires a higher understanding of hardware and software.
Refrain from experiments and contact us. We restore disappeared partitions quickly and reliably.
Possible causes of physical defects
Hard disk (HDD), hard disk
- Age / operating hours (mechanical wear due to friction of the components)
- Inferior quality
- Current overvoltage
- High heat generation inside the housing with poor or missing heat dissipation
- Vibration eg. by falling down (very susceptible)
- Humidity
SSD (Solid State Drive)
- High number of write/erase cycles (TBW “Total Bytes Written”). This means that the SSD only “ages” with the number of write/erase cycles.
- Inferior quality
- Current overvoltage
- High heat generation inside the housing
- Vibration (less susceptible than HDD)
- Humidity
Do not turn on your computer again if you are affected by data loss and refrain from risky experiments. Instead, put the recovery of your important data in qualified and trustworthy hands.