Who bears the cost of repairing or replacing the computer after its components burned out due to a new part brought by the owner and installed by the technician?

If the damage to the device was due to a defect in it and not from you, then neither you nor the shop owner are obliged to bear the cost of the damaged parts. However, if it was due to you, then consider: 1. If it was due to your negligence or dereliction of duty, or performing a task you are not skilled at, then you must bear the cost of these parts. 2. If it was due to an oversight or error without negligence or performing a task you are not skilled at, then you are not obliged to bear the cost of these parts, because you are a private employee (ajir khas), and a private employee is not liable for what is damaged in his possession unless he was negligent.

If you are not obligated to bear the cost of these parts, is the shop owner then obligated to compensate its owner? There is a disagreement regarding this, but the majority of scholars hold that he is liable.